Cards post on this thread is as good as it gets. I'm not sure if my comments are an extension of an already fine answer or possibly redundant thoughts on the subject. I'll leave the meat of the subject alone and offer my thoughts on punishment versus reward.
I have used both and my initial response is the right way to handle it depends on the individual team and no black or white answer will be correct. One twist I have always used is we would run if we won----not if we lost. I referred to it as our victory lap and we would run from home to 1st in a sprint one at a time while we cheered each player for a job well done. The first few times the girls thought it was stupid but they finally bought into it and took pride in it. Yes, I have punished but never if they gave it an "all out" effort. We got outplayed by better teams at times but quickly acknowledged them in our after game review. I was quick to point out it was only THAT game. We get ourselves more mentally prepared and take our "A" game to them next time we'd be running our victory laps right now. I tried to teach being humble in victory and respectful in defeat. I always searched out the best and offer to play them any time. I wanted the girls to see the confidence I had in them throughout the course of the season in hopes it would have them mentally ready for the challenges at the season ending tourneys that, in my eyes, really mattered.
I mentioned that I have punished. Does it ever work? I can share a short story that may give you something to think about. A larger local tourney that had the bulk of our team actually playing in their own backyard had us excited about playing in front of a hometown crowd, something you don't always get to do in travel ball. After a great start on Friday night and a good run on Saturday, we had advanced to the final game in the winner's bracket Sunday morning. A close encounter left us on the losing side by a run with a 1-game break before playing in the loser's bracket final. That game started badly and got worse with every pitch and every play. The girls fell apart and couldn't field or throw a ball. We wore out 3 pitchers trying to finish a 5-inning rout. In front of an entire community this 16u bunch looked like 10 yr old still trying to learn how instead of playing up to the hype the local community had come to hear and expect. After the game I discussed the issue with staff and felt we couldn't let them go home like this. We had the kids go tell the parents that we were going to fix this and meet us behind the outfield fence. There, we had the girls line up and throw to each other, back and forth, till they could do it as a team without dropping or missing a ball by all for at least 5 minutes. We went back to the basics of throwing, following thru, and catching while watching the ball into the glove each and every time. We threw out there with the championship game going on and the community able to see us for the length of the entire championship game. I told them I had all day and if they needed to stay till dark, each and every one of you fine athletes will still be here throwing till we get this part of your game fixed.
Cruel and unusual punishment? Didn't need to be that way. They made it that way. Parents came and wanted to get their kid and leave. I answered with if you go don't ever come back! They walked away. Painful to watch. As a follow up; we played 2 more tourneys after that and trophy'd in both. The next 2 years of high school ball they all ended up being shining stars at their respective high schools. Personally, I never observed ANY of them make a bad throw or miss a ball in a game. Do they hate me? If they do they have hidden it well over the years. lol. Did it make a difference? In that case I believe it did as that fall we had more local girls brought to our tryouts than ever before. Even if the kids didn't like it, parents seem to accept it.