Die Erfolgschance ist gut.

Because Erfolgschance is a feminine noun in German.

The key part is Chance, which is feminine: die Chance.
In German compound nouns, the last part usually determines the gender, so:

• der Erfolg = success
• die Chance = chance
• die Erfolgschance = chance of success

So the article has to be die.

German very often combines nouns into a single compound noun.

So instead of writing something like success chance as two separate words, German joins them:

• Erfolg
  • Chance = Erfolgschance

This is completely normal in German. The last part, Chance, is the main noun, and Erfolg modifies it.

Because all nouns are capitalized in German.

So in this sentence:

• Die = article
• Erfolgschance = noun → capitalized
• ist = verb
• gut = adjective

This is one of the easiest ways to spot nouns in written German.

Because ist is the 3rd person singular form of sein (to be).

The subject is Die Erfolgschance, which is singular, so German uses:

• ich bin
• du bist
• er/sie/es ist

Here, die Erfolgschance is grammatically like sie (she/it for a feminine singular noun), so the verb is ist.

Because gut comes after the verb ist, so it is a predicate adjective, and predicate adjectives do not take adjective endings in German.

Compare:

• die gute Erfolgschance = the good chance of success
  
  • adjective comes before the noun, so it gets an ending
• Die Erfolgschance ist gut. = The chance of success is good.
  
  • adjective comes after ist, so it stays gut

This is very common:

• Das Wetter ist schön.
• Der Film ist interessant.
• Die Idee ist gut.

It is understandable, but many native speakers would probably use a slightly different phrasing depending on context.

Common alternatives are:

• Die Chancen stehen gut.
• Die Erfolgschancen stehen gut.
• Die Chance auf Erfolg ist hoch.

Why? Because with probability or likelihood, German often prefers words like hoch (high) or phrases like stehen gut (are good / look good).

So Die Erfolgschance ist gut is understandable, but it can sound a bit less idiomatic than some alternatives.

Often, yes.

When talking about likelihood, German frequently uses hoch:

• Die Erfolgschance ist hoch.

That can sound more precise, because in English too we often say a chance is high, not just good.

By contrast:

• gut suggests the chance is favorable
• hoch focuses more directly on the probability level

So both can work in some contexts, but hoch may sound more natural if you mean actual probability.

The sentence follows the standard German main clause pattern:

Subject + verb + complement

So:

• Die Erfolgschance = subject
• ist = verb
• gut = complement

German main clauses usually place the finite verb in second position, and that is exactly what happens here.

Yes. The plural is usually Erfolgschancen.

So you could say:

• Die Erfolgschancen sind gut.

That would mean there are several chances, or it could refer more generally to the prospects.

This plural version can sound more natural in some contexts than the singular.

Yes, definitely.

Both are possible:

• die Erfolgschance
• die Chance auf Erfolg

The second version is often a little more transparent for learners because it is built more analytically:

• Chance auf Erfolg = chance of success

German often allows both a compound noun and a phrase with a preposition. Which one sounds more natural can depend on style and context.

A helpful rough pronunciation is:

air-FOLK-shan-tsuh

A few details:

• Erfolg has the stress on the second syllable: -folg
• sch sounds like English sh
• ch in Chance is pronounced like sh here because Chance is a loanword
• the final -e in Chance is a soft uh sound

So the whole word flows as one compound:
Erfolgschance.