I have gotten good at automating simply because I cannot do any manual process 3 times in a row identically, even with a checklist. A buddy-system checklist (someone else has the checklist and reads them off to me as I complete each step) will allow me to do it error free most of the time (to the point where repeating 3 times in a row is probable), but that doesn't make sense for most things I do on a regular basis; it's not like I'm flying a passenger airliner or operating in a surgical theater.

Here's an actual example of me trying to fill up the water glass on my office desk from the water filter in the kitchen; I have not developed a check-list for this; checklists reduce my mistakes, but do not come even close to eliminating them. This happened on Monday, but similar things happen all the time.

Attempt 1: Left the water glass on my desk

Attempt 2: Filled up the water glass, took a sip, placed it down on the counter, returned to my desk

Attempt 3: Picked up the water glass, took another sip, placed it back on the counter, returned to my desk

Attempt 4: Notice that the water glass is now 1/3 empty (2/3 full?) so I top it off and now finally remember to take it back to my desk.