Ideally, yes. But it must be done carefully and respectfully. Remember your social codes, and think before you speak.
Imagine this scenario: You've been invited to listen in on a make-or-break Zoom meeting for your organization — one that could land the next "big deal." Your boss runs the show and wants to groom you for bigger things, thus the invitation to attend.
The mood is good. The atmosphere is constructive, and just as your boss is about to close the deal— he misspeaks, confidently offering several numbers — but they're wrong, completely off. What do you do? Do you break your "listen only" status, and muster your courage to "correct the boss and save the day," or do you sit silently, and let the chips fall where they may?
In this example, it's a good idea to correct your boss, but it is all about how you do it. You need to inform your boss of the mistake artfully, with an authentic air of helpfulness. However, you must do it privately and quietly.
You can text or Slack your boss, or send a message via chat or whatever private channel you chose, but immediately send a message so that your boss can fix the mistake. If you're very clever, offer a reason why the boss misspoke — "Those numbers were from last quarter, just a build-up to show off how far we've come this quarter—the current numbers are…"
Alternatively, you could un-mute yourself and decide this is your moment in the sun — your chance to be noticed by all the heavyweights in the meeting. You have the correct information, after all.
So, you interrupt the meeting, your boss, and interject: "Excuse me, but my boss just gave the wrong information. I have no idea why. The correct numbers are…" You take a deep breath, mute yourself, and sit back to watch the accolades and "thanks for saving the day" messages blow up your Slack channel.
But instead of "pats on the back," you get a piercing look from your boss, and the senior-most person on the call asks, "And who was that?" Remember, your boss did you a favor by including you in the meeting; you're really not supposed to be there.
The senior person says thanks for the clarification, your boss continues, and the deal ultimately falls through. Your organization looked unorganized, disrespectful, and misinformed. Who knows, maybe the deal was always going to fail; you'll never know. But what is now apparent is your opportunistic tendency and total lack of respect.
If only you'd contacted your boss quietly, you think, as you search for your next job. You could have been a hero instead of the scapegoat — you flew too close to the sun. The lesson here: Be empathetic. Put yourself in your boss's shoes. Would you like to be corrected publicly?
To answer your question, "Is it ever okay to correct your boss?" Yes, but remember your social codes. Remain respectful of your boss, your organization, and your position, and you'll keep climbing toward your goals.