Oh you are not alone at all!
Each of us have our own standards and for most of us, they are something to strive to. Part of it is we are so close to the work, both in time and in distance. Personally, I find it rather reassuring that I've never had to deliberately put in a mistake, they just happen naturally for me and I've learned to accept it. After all, when does it really matter if all 4 sides of a quilt are exactly the same? Now, a wall hanging might be different but it's on a bed, and folded up it is good enough.
I love the planning and piecing, I'm not so good on the quilting. My usual self assessment is "another perfectly fine top ruined by indifferent quilting". My technical skills aren't so bad, but there's a whole bunch of issues from equipment to physical space to physical health, but some of it is that I just am not very inspired in my choices of quilting. I have so many tops ready to be quilted down I finally had to do some things, and the first was to analyze what my issues and constraints are. Biggest are budget and space -- and both are small. I've managed to get some free/low cost things that I hope will help -- but just as I got everything set up, my machine decided to go to the shop.
When it gets back, I'm going to be telling myself a lot of finished is better than perfect, and no one but me knows the "perfect" finish I am so far unable to produce.