I used one long arm quilter and when I received the finished quilt, it was terrible. First, the back was upside down. Everything had been marked and both the front and back had obvious directional prints. I could have lived with this, but.... On the back there were over 30 significant areas (1 inch or longer) where the bobbin thread had looped up like eyelashes. When I contacted her, she denied it. I offered to send pictures and she finally agreed to redo the quilting. It was only a simple meander pattern.
She said she would remove the quilting, but I didn't trust her to do that without damaging the quilt, so I undid the entire thing! It was lap-sized and it took me several hours to remove it all.
I returned it and she re-did the quilting. This time she paid more attention to what she was doing and it was fine. Needless to say, I found a new quilter! lol
If you aren't happy, I would remove it. But, it is time consuming.