You've put into excellent words what I have done my whole life. Intent matters but it isn't sufficient. If you "meant to be on time" but weren't, you failed. Simple as. You don't need to lash yourself about it but too many folk are ready to give themselves a pat on the back for good intentions, or trying but failing, etc.

If you say you're gonna be somewhere, show the fuck up. Anything short is a miss. Failing to account for that makes you an asshole, IMO.

If you’re interested in the subject and want to read more, the concept is commonly called “outcome oriented” vs “process oriented”.

A LOT of workplace conflict arises out of outcome oriented ppl having to work with process oriented people.