That's a really personal decision. I have found that when I'm frustrated or don't like what I'm working on, it absolutely kills all enjoyment and I go into a funk. Not good at all for my mental health.
Having said that, I once made a top that I finished but found disappointing, so I gave it away to a friend who is a quilting maniac; she quilts about 30-40 quilts a month and gives them all to charity. She quilted my top and showed it to me, and I loved it. I did regret giving it away but I don't go back on my promises, so I thanked her for turning it into something beautiful and sent blessings to the eventual recipient.
If you don't like it, give it to someone who does, let it bless someone else.