Why are Dells so difficult and proprietary?

I'm sure you have noticed this if you've worked on any Dell systems.

They are proprietary - which means that they make their own parts, and their computers are designed to only accept those specific dell parts! This is very aggravating!

For instance, if you work on a Dell that has a bad power supply.. you have to get a specific dell power supply to replace it. If you have to replace your Dell motherboard..than you must get the specific Dell model motherboard replacement for it to match up with your Dell case. Most of the front panel power buttons for Dells have a special power cable that must match up to a special port on the motherboard. It's just ridiculious!

I have to give my clients a $300 quote for motherboard replacements... and then they just decide it's cheaper to buy another computer... and guess what Dell... they are not getting another Dell!

If I buy a pre-built computer for a client I usually get HP's or an offbrand such as Systemax. This way if something goes bad in the computer it can be replaced without too much grief. Why don't Dell realize this is giving them a bad rep? Come on people!