Let's turn that on its head:
You've focused exclusively on magic, and now you find yourself in a dungeon where you can either face a huge tanky monster that you can't possibly tank, or you must sneak past him, which - no - you can't do that because you didn't have the clairvoyance to invest in some stealth skills. Now you're unable to progress in the game.
You're a frost mage, and this required dungeon is literally impossible to finish because the boss at the end is 100% frost resistant. Oops. (Actually, this kind of reminds me of the perils of speccing full frost sorceress in Diablo 2)
You're playing a low-charisma class and the only way to progress in the game is to convince an NPC to cooperate, so you spend hours and hours and hours reloading the game, hoping for a natural 100 because that's the ONLY way you'll ever get a successful roll and get past this horrible part.
Why even play at this point, when your success is based on your luck in choosing "the right" skills to complete the game? Or you could use gamefaqs, and lose all the discovery aspect of the game...
You can make arguments like this either way to support your viewpoint, but at the end of the day, different people have different ideas of a fun time. As a game company, you'd be better served to listen to a wider range of gamers.