1. They have some interesting stat or fact about their career or held some kind of unique record for a few minutes.
2. If they don't have that interesting bit of trivia then I have to highlight something of note about the photo, the autograph, or what's going on behind them on the card.
For this card:
#99 Mark Belanger
I'm overflowing with the the first category...so much so I'm a little ashamed that I don't remember every hearing Mark Belanger's name before. First thing first, his nickname, The Blade, has got to be easily a Top 10 all-time list somewhere of cool nicknames.
Before the rise of Cal Ripken, Jr. he held the Orioles records for games played, assists, and double plays by a short stop. He was an 8-time Gold Glove winner but was atrocious at the bat. In 1970 he was the Triple Crown winner in reverse by finishing last in batting average [.218], home runs , and runs batted in  through 145 games.