Another area where the PC is consistent where the console is not is with your input device that you use to play the game. A PC can have one joystick, game pad, or mouse that works for all of your games regardless of what company the game is made by. The console on the other hand, has a different controller every time it upgrades with a new system. The exception to this is with the transition between PS1 and PS2, where the controllers are the same, and there is even some backward compatibility. For the most part the PC wins the consistency battle, and consistency is something very important to consider when thinking about what kind of platform to purchase for.
Consoles can offer a different type of consistency.
A Console company like Nintendo has definitely demonstrated consistency, as well as Sega, and ever since Playstation hit the industry, it has been consistent too. Very rarely does a video game company drop off totally, but it has happened. Atari is nowhere to be found. So in this case it all depends on what you would rather do. If you don't want to have to upgrade your computer, you can still stick with buying a new console every couple of years to keep up with the latest and greatest breakthroughs in the industry.