Some EXE's it is determined to run them with UAC, just cause they have the name Update or some other keyword. And this behavior can't be disabled without using their compatibility tools.
So like, you download a exe archive file, and you want to run it, but you would rather Windows run it as a normal user. Not possible, it will insist it is run with UAC.
Making UAC royally useless. XP was actually better you could right click and run an EXE with limited permissions. You can't do that anymore.
Don't believe me? Try it, grab any EXE, rename it to "update" and try and run it, you will get a UAC prompt. This also happens if the "original filename" had one of the keywords in it.


-Edit
See solution here
http://www.techrepublic.com/forum/discussions/102-393381-3690114