B- Work

Hi Brooke,
I always do B- work and never improve it. When I have to work on something and hone it and perfect it, I get completely agitated and I guess my thought it I can’t do this. So I slapdash most of my life and then judge myself really harshly. So, my question is, is there a way to move on from B- work to work that I am proud of? If I say it’s good enough it is? But it isn’t and I know that. I see people that do work thoroughly and I want to be like that, but feel like I am not.
Any suggestions?