It's about "enough"
But why do we compare?
Am I good enough?
What do I do about it?
Comparison serves a useful function, if it is used properly. If it is misused, it can kill one's spirit.
We all like to feel good about ourselves. But when we use unreasonable standards and have unmeetable expectations, we are on the road to hell. When we have a useful viewpoint, then we will feel good about ourselves.
We evolved to compare, so that we could assess our capability to survive and/or meet criteria that affected our survival. Like many other evolutionary abilities, it can be misused in today's different environment where we are not in life or death situations 99.9% of the time and where we are no longer dependent on others liking us.
IT'S ABOUT "ENOUGH"
It makes no sense to compare how well off you are with some (unrealistic) standards set by commercials, movies, the culture, or your false assessment of the perfect lives of others.
There is no basis for setting a standard of “enough”, as in "I'll be happy when I get (am) enough or good enough." (What is actually the quest is to not be “not enough”.) But there is always more than enough, if we set our standard at “enough to survive and be able to seek what we want”. If we do that, then we can appreciate everything we have above that standard of "enough" - and we are able to be at happiness.
Though we "perceive" that we are vastly inferior to someone else, the truth is that you are much closer to being "the same". If someone else becomes a doctor and you are a janitor, you still have 99% of what they have (in terms of dna, body functions, emotions, potential fulfillment, etc. – even monkeys have at least 96% of the dna of humans).
BUT WHY DO WE COMPARE?
In today's world, it is irrelevant to compare. All that matters is that we have the ability to make decisions and to use our rational brains to get "enough". We are so blessed with what is actually lots of capability far beyond what we need to survive and thrive.
Oh, I almost forgot: why do we compare?
We had to "stack up" in the old tribe, so we could safely feel that they wouldn't kick us out, plus the alpha male or alpha female would get the best. But we no longer need the tribe to protect us, as we have everything already provided by the "big tribe" (highways, cars, supermarkets, etc.). And if we aren't covetous of "more", we realize that we don't have to be the alpha to get a perfectly good relationship and good friends - we can attact them by being a person who uses straight thinking and has good character. See Suffering And Struggle to see what coveting "more" can do for you! There is no legitimate function in pejorative (judgmental) comparing, whether it is about us or others. We need only realize that we have sufficient power to handle our lives on our own, without comparing.
AM I GOOD ENOUGH?
Comparison is an extension of the childhood question of "Am I good enough?", good enough to be loved (so that I'll be fed and won't die).
It is an old recording in our brain that one keeps on playing over and over and not getting good results from, so it would make sense to stop doing that! (Duh!)
The recording "matches" up with something in the current situation and then we're off and running, repeating the same actions on the recording and experiencing the same emotions, usually negative ones.
WHAT DO I DO ABOUT IT?
I don't deal with it separately here from other beliefs as it is just a variation on the "not good enough" syndrome. As in the other related beliefs, it involves an unfair standard and then a set of beliefs around what it means to you that will "hurt" you.
Everything we do we do for the reason that we think we will get something out of it.