As a kid I trained myself to keep track of time through using the 15m beep on my Casio watch.
Eventually I was quite accurate on the current time, rarely missing by more than a minute, but at some point it felt like it wasn't really helping me since I had the watch anyway. It also was too weird for becoming a party trick (first time I admit to learning this), and didn't help with the idea that I had just wasted X minutes of my life between any 2 moments I thought about time or checked it without having done something useful, so I ended up disabling that.
Eventually I was quite accurate on the current time, rarely missing by more than a minute, but at some point it felt like it wasn't really helping me since I had the watch anyway. It also was too weird for becoming a party trick (first time I admit to learning this), and didn't help with the idea that I had just wasted X minutes of my life between any 2 moments I thought about time or checked it without having done something useful, so I ended up disabling that.