@ Hapimeses
Microsoft uses many different drives, but particularly one model is well known to be extra prone to disc scratching. But not everyone who suffers from disc scratching issues has this drive. Most scratches are minor, but accumulate over time and then cause problems. Some scratches are the notorious deeply carved circle, which is usually caused by console movement.
The problem is also the speed at which DVDs have to spin inside the 360, they are originally PC drives and on the PC they aren't continuously used for playing DVD based games. A slight movement of the console can cause disc scratches and isn't covered by warranty according to Microsoft (So IMO not really a console suitable for small kids or for areas enduring turbulence). Over time DVD drives continuously spinning at such speed will wear, screws may loosen causing more vibration causing more problems, etc.