Al-Da'ala Al-Sahadith and the Sahaba

Once the decision has been made the sahaba were not criticized after that for what happened. Once you make up your mind properly then halaas don't look back and our professors said none of you should say if only i had done this then that would have happened but rather say kadadad al-la ha'masha al-falaal. Say whatever al-la has willed has occurred because saying what if opens up the door to shaitlan.