Why do Dell owners have so many problems?

Is it because Dell sell so many computers?
Is it because they customise the BIOS heavily?
Is it because Dell owners use their computers more heavily?
Is it because they are built-to-order and this makes quality control harder?

Or something else?

What issues do you have with your Dell? Here in Greece Dell has a very good support reputation like coming to fix it on the spot and if they cannot they take it for repair free of charge, as long as is under Warranty of course. As for the locked BIOS, unfortunately, this is a known issue of most laptop models, not only Dell. They let very little freedom to the end user to change settings in BIOS. Most are only for enabling/disabling UEFI mode, enable/disable some devices or USB charging when off, that kind of stuff. No comparison to the BIOS settings of an average desktop computer.