Change direction without a lecture about whose fault the first direction was.

When a plan has to change, there are two separate tasks: deciding what happens now and establishing who was wrong before. Combining them makes the change expensive, because everyone starts defending their position instead of moving. The review can happen later, quietly, and often does not need to happen at all.

Announce the new direction plainly, without a preamble about how you got here. If something genuinely needs to be learned from it, take that up separately and in private. People move much faster when changing course is not also an admission.