No me gusta compararme con otras personas, porque comparar mis errores con sus éxitos no me ayuda.

They do two different jobs:

• me gusta: here me means to me. With gustar, the thing that is pleasing is the grammatical subject, and the person who likes it is shown with an indirect object pronoun.
• compararme: here me is reflexive and means myself.

So:

• No me gusta = I don’t like
• compararme = to compare myself

Together: I don’t like comparing myself.

Because when a reflexive verb is in the infinitive, the reflexive pronoun is usually attached to the end:

• compararse = to compare oneself
• compararme = to compare myself

You could also say:

• No me gusta compararme
• No me gusta me compare ❌

The second one is wrong because after gusta here you need an infinitive, not a conjugated verb.

Because gustar works differently from to like in English.

In Spanish, the thing being liked is what controls the verb:

• Me gusta comparar... = Comparing... is pleasing to me
• Me gustan los libros = Books are pleasing to me

Here, what is pleasing is the action compararme con otras personas, which is treated as singular, so the verb is gusta.

The subject is the whole infinitive phrase:

compararme con otras personas

That entire action is the thing that does not please me.

So structurally, the sentence is closer to:

• Compararme con otras personas no me gusta

But Spanish often places the no me gusta part first because it sounds more natural.

Because the verb comparar(se) normally uses con when you compare one thing/person with another:

• compararse con alguien = to compare oneself with someone
• comparar X con Y = to compare X with Y

So:

• Me comparo con otras personas = I compare myself with other people

Using a here would not be natural.

Because comparar mis errores con sus éxitos is being used as a noun-like idea: comparing my mistakes with their successes.

In Spanish, an infinitive often works like an English -ing form:

• Fumar es malo = Smoking is bad
• Leer ayuda = Reading helps
• Comparar mis errores con sus éxitos no me ayuda = Comparing my mistakes with their successes doesn’t help me

So comparar is correct because it is the subject of no me ayuda.

That me means to me or me as the person affected.

• No me ayuda = It doesn’t help me

The subject of ayuda is again the whole infinitive phrase:

comparar mis errores con sus éxitos

So literally:

Comparing my mistakes with their successes does not help me.

Sus refers to otras personas.

So:

• mis errores = my mistakes
• sus éxitos = their successes

Even though otras personas is plural, sus can mean:

• his/her
• your (formal)
• their

Here, context makes it clear that it means their.

Both are possible, but sus éxitos is shorter and more natural here.

Spanish often uses possessives when the owner is already clear from context.

So these are similar:

• comparar mis errores con sus éxitos
• comparar mis errores con los éxitos de otras personas

The first one sounds more concise and natural in this sentence.

Because otras personas here means other people in a general sense, not a specific group already identified.

Spanish often omits the article in broad, general statements:

• Hablo con amigos = I speak with friends
• No me comparo con otras personas = I don’t compare myself with other people

If you said con las otras personas, it would usually mean with the other people in a more specific situation.

Yes, porque is correct because it means because.

Spanish distinguishes several similar forms:

• porque = because
• por qué = why
• el porqué = the reason
• por que = less common, used in specific structures

Here the sentence gives a reason, so porque is the right choice.

Yes, No me gusta compararme con los demás is very natural, but a los demás would not be correct with compararse.

The natural options are:

• compararme con otras personas
• compararme con los demás

Both mean roughly to compare myself with other people / others.

The speaker is talking generally, not about one specific mistake and one specific success.

• mis errores = the mistakes I make, in general
• sus éxitos = the successes other people have, in general

Using the plural makes the idea broader and more natural in this kind of reflection.

Yes. That version is also correct and may even sound slightly clearer because it repeats no me ayuda before the explanation.

The original sentence is already natural:

No me gusta compararme con otras personas, porque comparar mis errores con sus éxitos no me ayuda.

Your version is just a small stylistic variation:

No me gusta compararme con otras personas porque no me ayuda comparar mis errores con sus éxitos.

Both work.

• comparar = to compare
• compararse = to compare oneself

So:

• compararme con otras personas = to compare myself with other people
• comparar mis errores con sus éxitos = to compare my mistakes with their successes

The first is reflexive because the speaker is comparing themself. The second is not reflexive because it is about comparing two things: mis errores and sus éxitos.

It is acceptable here, especially because the second part is a longer explanation. But in many cases, Spanish does not require a comma before porque when it introduces a direct reason.

So you may see both:

• No me gusta compararme con otras personas porque comparar mis errores con sus éxitos no me ayuda.
• No me gusta compararme con otras personas, porque comparar mis errores con sus éxitos no me ayuda.

Both are understandable and natural. The comma gives a slight pause.