Firing crappy workers

ARGHHHHH -
had to fire a worker y'day and it is just so discouraging to me.  30 yo guy who had been showing up, working hard, going home, for 3-4 days per week over the past 3 months. Task by task seemed reliable, friendly, interested in regen ag, good with animals, built some trust, completed some key projects.... We have community lunch on the farm. I care for the people I cook for, and share a meal with...

I was gone for several days to an event out of town.  We had a plan for what would happen on two days of work while I was gone.

I returned home to find the farm truck with 450 extra miles on it, smelling like weed.
Card in the truck (for gas) used for gas and also for $75 of personal purchases at Walmart and other shop, no comment, no explanation; I found it by checking the card account. No work done on the two days we agreed.  Specific tasks with specific timing criteria ignored, with unfortunate consequences.

This is such a bummer.  Disappointing.
(I really do believe that everyone is doing their best all the time, and if they could be doing better, they would. And I have made my share  --some might say more than my share--  of bad decisions, poor choices and regrettable actions in my time...  so I understand that sometimes things go sideways...)
Ugh. Once someone shows you who they are, then it is there to be dealt with.  It is really unwise to ignore, because it happens again.
There are the situations where (maybe it's not so bad???) it seems like a clear Come-to-Jesus talk about the problems would ensure that nothing like this happens again. I would love it if my experience showed that this worked - but that has not been my experience. Whatever the 'IT' was, it happens again, on a bigger scale and perhaps with more subterfuge.

So he is fired and I am sad.  I like people. I want them to succeed and thrive.  We have had some GREAT peeps out here at the farm.... And when it does not work out, I am really sad.

Anybody with comments to share on this? I could use some encouragement. Confidence in humanity is having a drought moment...

Giving folks too much trust never seems to work out.

We recently went on a trip and dear hubby and I had a long discussion about locking things up.  I won, things got locked up.

I am sorry to hear that this happened.