overhang

so i've done about 13 class 2 restorations so far, and i'm starting to see that some of them have overhang (radiographic). i'm puzzled as to why this happens since i follow the procedures to do the restorations and check my restorations with floss afterwards (no breaking in the floss). do you guys often find yourself having to redo some/a lot of restorations? definitely a confidence breaker
Source: Student Doctor Network - Category: Universities & Medical Training Authors: Source Type: forums