It happens on all versions but on PC due to OS caching hard drive accesses (file buffers and directory file listing caching) and other features for optimization it goes nearly unnoticed.

It's more of annoying on PS2 and XBOX360 because these machines have tight memory restrictions thus caching is not possible (or if it's possible, it's very limited) which in turn makes hardware related slowdowns (hard drive and on XBOX360 case disc seek times) very prominent/annoying.