In the context of taking an action, that is making a decision or choice and acting on it, how can you determine if it was right (a good choice) or wrong ( a bad choice).

Feedback recieved during the decision making process can help.  Of course, results from  multiple sources can lead to a variety of input both postive and negative. Confusion reigns.

The goal should be to focus on objective feedback based on tangible metrics, things you can definitively measure.  This requires a clear statement of outcomes.

Strategic or Tactical Time Frames

Analysis can be complicated by point in time outcomes.  Is it about short, medium or long term.  Or even all three or a combination thereof.

Further complicating determination of right or wrong can be underlying moral or value based considerations associated with the decisions results.

For Example

In 1948 the Russians decided to block the Western allies tranportation access to west Berlin, thus starving and otherwise inconveniencing the western allies (and the general population) such that they would decamp and leave Berlin under complete Russian control.

For the Russians this was a moral and just decision.  Not so much for the Western allies.  Was the decision right or wrong?   At the time the answer to this question depended somewhat on where you lived, your politics and values.

Should the US restrict visitors and immigrants from selected predominantly muslim countries? is it right or wrong, can it be justified?

My own opinion is this action is both wrong and unsupportable.  However, there are those with a contrary powerful argument.   Perhaps the best way is respectful dialogue.  Maybe we can figure it out.

Or maybe, as occured in the case of the Berlin blockade, one side figures out how to overcome the other.  Guess who stayed in Berlin without starving.