I'm trying to improve my 10k time.
So I make a 10k (approx) run but I'm not stopping at 10k exactly, I'm stopping it at say 10.4K.
The PR is showing the total activity time, including the 0,4K instead of stopping at exactly 10k.
I suppose you're considering a wrong purpose.
It isn't me who is considering wrong purpose, as it is not me who came up with it. I just explained to you how it works. You may not like the explanation, but that won't change the current state of matters.
The purpose is crystal clear: tell me how long took me to do a 10k run, not a 10,4k run.
Obviously the author of the solution had a different purpose in mind.