This actually happened to me once - I walked for way longer than I expected (I had looked at a map just to get directions not caring much about distances), but

This actually happened to me once - I walked for way longer than I expected (I had looked at a map just to get directions not caring much about distances), but anyway it was an errand I absolutely had to do that day, knowing in advance how long it was going to take wouldn't have helped me (except maybe psychologically). Now, I'm not defending my actions, I just gave the example to see I was not exaggerating.