“Just throw strikes”. We hear this too often. Baseball and softball are quite different, but recently I went to a huge 12U baseball tournament. I heard the opponents exhorting their pitchers to throw strikes. I watched the team we were following blast 5-6 homeruns per game.
Eventually our team found itself in very elite company, after the majority of teams had been eliminated. Suddenly they faced a very different pitcher, who barely touched the corners, threw pitches that looked like strikes before they moved off the plate, and he changed speeds very well. Everything changed. There is a huge parallel to softball.
The key is not just throwing strikes, but being able to command the zone, entering it when you want, but leaving it just as quickly. Keep the batter guessing so that, if she happens to make contact, it is not in the way she was hoping.
It is not a matter of trusting the defense, but a matter of making their job easier. When a ball is hit, three things can happen. Two of them are bad. First, reduce the number of times the ball gets hit. Second, make sure that it never gets hit on the nose so the defense has the very best odds of making an easy play.