If a teammate’s only mistake is trying something new, protect them. Punish that and nobody tries anything again.

Teams learn very quickly which risks are allowed. Punish an honest attempt and you teach everybody that the safe move is doing only what they were told, which looks like discipline for a while and then looks like a group that cannot adapt. The failed attempt cost you one thing. The silence afterwards costs you every idea nobody bothers to mention.

When somebody tries something and it does not work, say first that trying was right. Separate the decision from the outcome out loud. Then work out together what you would change, without taking the freedom away.