No, hoarding does not successfully express the desire to better yourself. Merely a desire to have more stuff.
I think the desire to better yourself and to obtain the power necessary to keep bettering yourself is a natural and commendable trait. Only when this comes at the expense of others is it irresponsible.
Come to think about it.. Human greed
is freaky

My previous 'better yourself without caring about others' indeed doesn't cut it.
I saw at a documentary about a tiger mom last week. 3 cubs, cute as hell

At some point tigermom bettered herself and she didn't really care about what that little monkey thought of her plan. She bettered herself, killed a monkey in the process but still I can't call that greed. Even when that monkey was just 'a lesson' for the cubs; They didn't eat it.
So here's another shot
Greed is bettering yourself
beyond reasonable. While [not caring about] worsening others.