Several years ago I took a very pricey class from a very well known quilter. She hated the fabrics I picked out (I shopped my stash), made me rip out my first block and sew it with fabrics she preferred (I didn't think much of her combination and the colors would not work in my home - I had to buy some fat quarters to make her happy). She told me I was working too slow and that I had to have perfect 1/4" seams(for me speed = wonky seams) -- by the time the 6 hour class was over I had made one block while the rest of the group had made enough blocks for a quilt. I was a nervous wreck. I trashed the project when I went home and never made it (even though I liked the pattern).
Now I rarely go to classes, I try to use youtube to learn new techniques.