If as a leader you don't acknowledge a fundamental tension, then you've set up your subordinates for failure.

The task is secretly impossible and yet your subordinates are responsible for delivering it.

If you're distracted or busy, when the project fails it's easy to erroneously conclude not "the idea is wrong" but "the execution was wrong".

Sharing disconfirming evidence from the person responsible for executing a plan once it is committed can look like making excuses.

The people best situated to understand disconfirming evidence (e.g. how hard a given task actually is) are those executing on it, developing knowhow.

If people fear being blamed for execution issues, they might not share relevant disconfirming evidence.

That's why seeking disconfirming evidence from subordinates before committing to a plan is the best way to make sure you understand the forces in tension.