Blind stealing in poker tournaments can produce a number of positive outcomes.
I'm referring to those instances when a player open-raises before the flop with a primary goal of earning folds and winning the blinds (and antes, if in play) uncontested. That includes raising with medium-to-weak starting hands you don't necessarily want to play postflop, although any time you open with a preflop raise you should be thinking about how you want to continue should you be called or reraised.
The benefits of blind stealing begin with the addition of chips to your stack. Just one successful "raise-and-take" hand per orbit means you're accumulating exactly the cost of playing each round.