Because every swing doesn't have to be the best ball you've ever hit. You just have to get the job done.
It's a close game, runner on third, one out, bottom of 6th. We needed the run. I've got a 3-1 count. SS in in, 2B is at regular depth. Ball is probably a foot outside. I could just take the walk but, because it's softball, I know I can hit it to the right side. I thought I got a good chunk of it but it was nothing like my first three AB. 2B fields it, throws me out, run scores. The reason the walk wasn't better than a potential FC but run scoring out was because the guy behind me was fighting a hamstring and had already hit into a DP. We win by 1.
I could have selfishly taken the walk and claimed "3 for 3 with a walk." But that's not really the point.
Point was I was smoking the ball by staying in my zone. Same swing, same contact on the barrel but, because I was leaning way out over the plate, the EV was much, much different.