Learn Hardcore German: In dieser Phase wollen wir testen, ob unsere neue Routine im Büro funktioniert. - In this phase we want to test whether our new routine in the office works.

Phase is feminine: die Phase.
After in you normally get:
- accusative if there is movement into something (where to?),
- dative if it is just a location or a stage (where?).

Here it means during this phase / in this stage, so it is a static situation → dative.

Feminine declension with diese-:

Nominative: diese Phase
Accusative: diese Phase
Dative: dieser Phase
Genitive: dieser Phase

So in dieser Phase is in + dative feminine → in dieser Phase is correct.

Why does the sentence start with In dieser Phase instead of Wir wollen in dieser Phase testen …? Does that change the meaning?

Putting In dieser Phase at the beginning does not change the basic meaning; it mainly changes emphasis.

German has a strong rule: the conjugated verb must be in second position in a main clause.

Both of these are correct:

In dieser Phase wollen wir testen, …
- First element: In dieser Phase
- Second element: wollen (conjugated verb)
- Third: wir
Wir wollen in dieser Phase testen, …
- First: Wir
- Second: wollen

The first version emphasizes the time frame / phase: In this phase (as opposed to some other phase) we intend to test.
The second version emphasizes the subject: We intend to test in this phase.

Why is it wollen wir testen after In dieser Phase? In English that word order would look like a question.

In English, want we to test would look like a question.
In German, it is different: the finite verb is always in the second position in a statement.

Sentence breakdown:

In dieser Phase (1st element)
wollen (2nd element – conjugated verb)
wir (3rd element – subject)
testen (infinitive, sent to the end because of the modal verb)
rest of sentence …

So the structure is:

[1st element] + [finite verb] + [subject] + … + [infinitive at the end]

It is not a question because the subject (wir) follows the finite verb in second position as part of a normal declarative word order with something else in first position. A yes–no question would move the verb to the very front with the subject immediately after it, e.g.:

Wollen wir in dieser Phase testen, ob …?

Why do we say wollen wir testen instead of just testen wir or using werden (like werden wir testen)?

All three forms are possible in German, but they express slightly different nuances.

In dieser Phase wollen wir testen, …
- wollen = to want / intend.
- This stresses intention / plan.
- Implies: This phase is for testing; that is our purpose.
In dieser Phase testen wir, …
- Simple present, no wollen.
- This sounds more like a fixed schedule or fact: we (actually) test in this phase.
- Less about intention, more about describing what happens in that phase.
In dieser Phase werden wir testen, …
- Uses werden as future tense.
- Grammatically fine, but in everyday German the simple present (with a time expression) is usually preferred.
- Wir testen in dieser Phase … already implies future when context is future.

So wollen wir testen is chosen because it highlights that testing is the planned goal of this phase, not just a neutral description of what happens.

Why is there a comma before ob, and why is funktioniert at the very end of the clause?

ob unsere neue Routine im Büro funktioniert is a subordinate clause (Nebensatz).

Rules:

Comma before subordinate clauses
In German, subordinate clauses introduced by words like ob, weil, dass, wenn are separated with a comma from the main clause:
- …, ob unsere neue Routine im Büro funktioniert.
Verb-final word order in subordinate clauses
In a subordinate clause, the conjugated verb goes to the end:
- ob (subordinating conjunction)
- unsere neue Routine (subject)
- im Büro (adverbial phrase)
- funktioniert (conjugated verb at the end)

So the pattern is:

ob + [subject / objects / adverbials …] + funktioniert

That is why the comma is needed and why funktioniert comes last.

When do we use ob instead of wenn or falls?

ob corresponds to whether / if (for indirect yes–no questions), while wenn and falls are if (whenever / in case) for conditions.

Use ob when:

You could answer with yes or no.
You are not stating a condition, but reporting a question or doubt.

Examples:

Wir testen, ob unsere neue Routine im Büro funktioniert.
→ We are testing whether it works (yes or no).

You would not use wenn here, because that would mean:

Wir testen, wenn unsere neue Routine im Büro funktioniert.
→ We (only) test *when our new routine works.
→ Completely different meaning: it becomes a *condition.

falls is similar to wenn in the conditional sense (in case / if), so it also does not fit here.

So: use ob to introduce an indirect question: whether it works.

Why is it unsere neue Routine and not unseren or unserer?

You need to match case, gender and number.

Routine is feminine: die Routine.
In the clause ob unsere neue Routine im Büro funktioniert, unsere neue Routine is the subject of funktioniert.
- The subject is in the nominative case.
Feminine nominative singular with unser- is unsere:

Nominative feminine: unsere Routine
Accusative feminine: unsere Routine
Dative feminine: unserer Routine
Genitive feminine: unserer Routine

So as nominative subject, the correct form is unsere neue Routine.

What is the gender of Routine and how would I use it in plural?

Routine in German is:

Gender: feminine
- die Routine
Plural: die Routinen

Examples:

Singular:
- Die neue Routine funktioniert gut.
- Unsere Routine im Büro ist effizient.
Plural:
- Die neuen Routinen funktionieren gut.
- Wir wollen mehrere Routinen testen.

What does Routine mean here exactly? Could I use Ablauf or Gewohnheit instead?

Routine in this context means a procedure / process / standard way of doing things at work.

Rough nuances:

Routine
- Often used in office and work contexts for standardized procedures.
- Neutral tone, a bit bureaucratic or technical.
Ablauf
- Literally: sequence / course / flow, e.g. of a process.
- Ein neuer Ablauf im Büro = a new workflow / process.
- More about the order of steps.
Gewohnheit
- habit, something people are used to doing.
- More personal/behavioral, less formal than Routine or Ablauf.

You could say, for example:

In dieser Phase wollen wir testen, ob unser neuer Ablauf im Büro funktioniert.
→ Focus: process / workflow.

Routine is very natural and common in business German for a new standard procedure.

Why is it im Büro and not ins Büro? And what exactly is im?

im is a contraction of in dem.

Büro is neuter: das Büro
Dative singular: dem Büro
So in dem Büro → im Büro

Case choice:

in + dative = location (where?)
in + accusative = direction (where to?)

Here it is about a location (in the office → where?), not movement into the office, so you use dative:

im Büro = in dem Büro → at/in the office

If you said ins Büro:

ins = in das (accusative)
That means into the office (movement, direction), e.g.:
- Ich gehe ins Büro. → I go into the office.

In your sentence, you are not moving anywhere; the routine functions in the office, so im Büro is correct.

Could I move im Büro to another place in the subordinate clause, for example ob im Büro unsere neue Routine funktioniert?

Yes, German word order inside the middle of a subordinate clause is quite flexible.

All of these are grammatically correct and natural:

ob unsere neue Routine im Büro funktioniert
ob unsere neue Routine funktioniert im Büro (less common, more marked)
ob im Büro unsere neue Routine funktioniert

The general rule for a subordinate clause is:

The subordinating conjunction (ob) comes first.
The conjugated verb (funktioniert) comes last.
Elements in the middle (subject, objects, adverbials like im Büro) can be reordered for emphasis or style.

Most neutral and typical is the original:

ob unsere neue Routine im Büro funktioniert.

Why do we use the present tense funktioniert when we are talking about something we will test in a phase (i.e. future time)?

German often uses the present tense to talk about the future, especially when there is a time expression or when the future meaning is clear from context.

Examples:

Morgen testen wir die neue Routine.
Nächste Woche haben wir ein Meeting.

In your sentence:

The main clause already indicates planning / future: In dieser Phase wollen wir testen.
The subordinate clause states what is being tested in a general way: whether the routine functions (works) in principle.

So funktioniert expresses a general property: whether it works (or not), which fits well with the present tense. You could technically say funktionieren wird, but that sounds heavier and is usually unnecessary.

Is there any difference between testen, probieren, and ausprobieren in a sentence like this?

Yes, there are nuance differences:

testen
- More formal/technical.
- Often used in work, IT, science, business: to test something systematically.
- Fits very well with Routine and Phase.
probieren
- Everyday word; often used for trying out food, clothes, or quickly trying something.
- Wir probieren eine neue Routine im Büro. is understandable, but sounds more casual and less systematic.
ausprobieren
- Very similar to probieren, but emphasizes trying out in practice.
- Wir wollen eine neue Routine im Büro ausprobieren.
  → more like “try it out and see what happens” in real life.

In a structured, business-like context where you speak of phases, testen is the most neutral and appropriate choice.

Could I say In dieser Phase testen wir, ob … instead of In dieser Phase wollen wir testen, ob …? How does the nuance change?

Both are grammatically fine, but the nuance shifts:

In dieser Phase wollen wir testen, ob …
- Highlights intention / plan.
- Suggests: the purpose of this phase is to perform tests.
In dieser Phase testen wir, ob …
- Sounds more like a schedule or description of what actually happens.
- Implies: as a fact, this is the phase in which we test.

In many contexts they can be used almost interchangeably, but wollen makes the planning aspect more explicit.