Is purposelessness the real defining characteristic of a loser?

There's an interesting contradiction I noticed here, when people questions whether they can turn their life around at certain age, most comments will say that it's possible, but in other threads, there seems to be a sentiment that "if you don't do x or have y at a certain age, you never gonna make it. Anything afterward will only be just a compensation".

Then I wonder what truly defines a loser here? The typical incel/NEET/loser is the ones without purpose and the ones without the hope that they can change their life around, they just mope.

But what about people are dealt with shitty cards in life and failing to achieve correct milestones at correct age?

Those people may not ever know 'social expectations' until they break free from their background. Those who have bizarro and deprived kind of tough childhood. I know of people who are homeschooled by conspiracy nut expats living in Cambodia, people who grew up in cults, Munchausen's by proxy, or just poor but they grew up in the middle of nowhere so they don't have a lot of peers like typical poors. No street smart, good family nor proper education for them.

A lot of these people indeed do have purpose and desire to change their lives when they manage to change their environment, they have goals... But they're 'loser by metrics'. They can turn their life around and get in good relationships or becoming financially stable with fulfilling as an adult, but they'll always miss what's expected in their youth.