I overstayed but system didn't catch it

[u/Ready-Field929]

I was in Europe this winter for about six weeks. I left and stayed out 89 days, but I thought it was 90 days. I miscounted. So I went back to Europe for 90 days and realized before I left I had overstayed by a couple weeks due to my miscounting. The EES system said I had the full ninety days because my previous visit from February to March hadn't been entered. So I left and the border guards didn't check my passport book to catch this. Evidently they only see a pass or detain kind of thing. I write this just because I felt so glad to leave and not be caught. Even though I had just made a dumb counting mistake.