Any CD I've ever burnt skips in my vehicles' CD player after playing a while -- usually starting around the tenth track and growing progressively worse.
No commercial CD ever skips in the same CD players, no matter how long it's been playing.
Why are the burnt CDs skipping? I've got a Lite-On burner, and have used different brands of CDs. I've used various burning apps, all with the same results.
The CDs don't skip in a home CD player or computer -- just in my two vehicles.