When most people say they'll do something, they really mean they'll try to do it, and they don't really worry too much whether they are successful or not, so long as they gave their best effort.
This has a hidden cost, since if you commit to someone and fail repeatedly, even though they may know you're doing your best, they will nevertheless lose trust in your integrity, and the next time you commit, they will not really believe that you will follow through.
Bob joins a Teams call 10 minutes late. It goes well but he's not aware of the end time and it goes 30 mins over, which impacts 2 other people's schedules. He then agrees to send an email with the agreed action points by COB, but doesn't get to it until the following day, causing people to wonder if they should be following him up. One person SMSes him about it "Don't forget that email", but he doesn't reply to it for over 2 hours, leaving the other person hanging.Figure: Bad Example - none of these things are that big a deal, but they add up to no one wanting to work with Bob
Jim has reminders set up on his calendar to make sure he makes it on time to his Teams call. With 10 minutes left in the call, he checks if people have a hard stop afterwards, and when he finds out 2 people do, he makes sure the remaining discussions that require those 2 people are prioritised so they can leave. He then agrees to send an email with the agreed action points by COB, but knows he hasn't got time to do it immediately, so sets himself a quick reminder on his phone to do it in 1 hour. Figure: Good Example - Jim has great professional integrity.