I'd say that a few things helped get me into pixel art. Around 4 or so years ago, we had got rid of internet, and I was left with basically a blank PC with nothing fun to do than open up MSPaint and doodle. So, for about a year (or two?) without internet and only drawing in MSPaint, I got fairly good at controlling the mouse when drawing.
A little later on, I started playing a game that everyone in my area was called "Well of Souls." It was a fairly cheesy MMORPG that was your standard grindfest with mediocre quests on the side, but the unique thing it had was the ability to make your own "skin" (appearance) for your character, which was basically four or five frames for each possible action your character did in a scene. Game sprites were a popular choice for making skins, so I got into sprite editing from there (mostly SNK sprites) as well as trying to make my own from scratch (based on a "stretch bunny" toy my friend had). That was about the time where I really learned all the little tricks with MSPaint, like all the things you can do with the right-click button.
Take that, and the fact that I became really interested in SNK/Capcom fighting games, as well as getting into the emulation of older games. These days, I'm trying to make graphics to make my own games, and some just for fun and for expressing myself when I'm feeling all artsy-like.