Avoiding Crochet Mistakes: Common Problems and Solutions

Dear users, dear authors,
Are there typical sources of mistakes in crochet? How can you solve them / get them under control?
It would be great if you’d like to share something about this. If you currently have a crochet problem, you can of course post it in the forum at any time. 

When crocheting in rows, it’s easy to gradually lose stitches at the edges because the last stitch of a row can tilt slightly downward, making it easy to overlook. You can avoid this by placing a stitch marker in the first stitch of each row; that way, when working the wrong side row, you’ll know where the last stitch is without having to count all the time. :-)