Yup. On the one hand, recruiting is hardly the rocket science of software engineering, and on the other hand, it's hard to imagine a more user-unfriendly system than Taleo, yet somehow they seem to dominate the market.
Silk Road and SuccessFactors are just as terrible in my opinion but seem to also have a healthy percentage of the market. I believe all these HR software systems follow a similar pattern of starting out solving a fairly simple problem, then as Sales brings in more and more disparate customers, the developers keep tacking on stuff until it is a hodgepodge mess.