White balance is important to your photos, but like so many things in life there's really no right answer. 

White balance, a combination of color temperature and tint, has a tremendous impact on the 'feel' of a photo's implied setting, so by adjusting white balance during post processing, you can dramatically change the time and season it looks like a photo was taken in.

The first shot shot below  (on the left) feels like a summertime evening after a rainstorm, bathed in pinks and oranges, while the one on the right looks like it was taken on a dim winter afternoon. I'd say the one in the middle is somewhere in between. 

You can make these adjustments with any photo, so if you have a photo laying around that looks too orange or too blue for your taste, it's an easy fix. If you're using a RAW file instead of a JPEG (as I was here) you'll be able to make much more drastic white balance changes, but most photos with weird WB need just a small tweak to change the look entirely for the better.