Why Customers Prefer CPANEL Over X X X

We have been getting a high quantity of requests for our VPS's with CPANEL preinstalled.

However, we feel that CPANEL uses way too many resources, and honestly its a bit expensive for what it does.

So, here's the deal, WHY CPANEL, and not Open source alternatives such as ISP Config?

Please give me some other Open Source (aka free), Web Hosting panels, as part of this poll!?

I personally always have favored doing everything on the 'bare' system, this is why CPANEL doesn't make too much sense for myself.

So, what is it about cpanel and plesk, etc thats so much better against the free options out there?