I'm still new at machine quilting and I'm still in the "oh, well, I'm just having fun and learning" phase. I'm making some quilts to give as gifts, so they have to be decent, though! I know after hours and hours of working on the same quilt, I'm pretty over it, and then I have to switch to another quilt or I'll tend to get sloppy.
I don't fret over little mistakes, like if I cross while meandering (because I'm still not very good at that!); I only rip out if it effects a portion of the quilt. I do have puckers on the front and on the back, but if they are bigger than 1 or 2 stitches, I rip it out. But if it's just a little one, I let it ride.
I'm hoping it will all be ok after it's washed and dried lol!