I think it's hilarious that the episode that's pretty much always regarded as "The Worst Episode" came out with the quote that sums it up so well.<--- Worst episode is everyone's fave. We just don't talk about it.
"The way I see it, every life is a pile of good things and bad things. The good things don't always soften the bad things, but vice versa, the bad things don't necessarily spoil the good things or make them unimportant." - The Doctor