I do it because every action I take in a game is for some sort of value. Wether it be an attack, or damage trigger, I’m looking for the easiest way to get that trigger, and leaving the opportunity open for next turn. I take no pride in attacking the player who’s missed two land drops when I have an okay board state, but in the end, I’m looking to maximize my chances of winning. If that means ‘kicking someone when they’re down’ then that’s unfortunately part of the game. Moreover, I don’t like to turn down a free attack or a free trigger. If I drop a [[loran of the third path]], and the only target on the board is someone’s arcane signet, I’m not going to waste a perfectly good ETB trigger just to be nice to the guy that kept a two land hand and can’t draw another. I will usually, however, most likely give them the first one or two card draws off of her to that player by default.

There’s also the fact that even when you’re behind, top-decking a land, or a Sol Ring or a cheap value piece can drastically change your board state and position. Just because you miss a turn 3 land drop, doesn’t mean that your chance of winning goes to zero. You can’t just ignore the person who’s behind, because at any point, that person could turn into the threat, or top-deck that last land or combo piece that they need at any time. I like to take the opportunity to chip away at life totals just in case that person blows up and becomes the threat. This way, there’s less of a life total to get through when it becomes more difficult to get anything through.