Users burned by low-quality freeware and shareware see it as a toy. Experienced managers look at the morass of e-mail folders, IRC logs, and CVS commits, wondering how anything ever gets done. But when you get right down to it, XP goes against conventional wisdom. I don't want someone looking over my shoulder and slowing me down, and I don't need somebody pointing out bugs. Customers can't be trusted to know what they want.
Conventional wisdom is based on experience, and therefore has some merit.
Where it misses the point is in its failure to grasp the concept that XP practices actually reinforce the traditional process, not degrade it. The open source connection Open source development has similar advantages to Extreme Programming, though the motivations may be different. In some cases, given the right motivation, they can even redirect development focus. These two methodologies overlap in some areas and lock horns in others. On the other hand, both approaches often have short release cycles, adding a few features and rapidly integrating user feedback.