I'm a sporadic/infrequent openstreetmap contributor, too - although I'm not second-guessing these contributions. Useless or not, I do use OSM all the time personally, so reason stands somebody before me did a good job and helped me a lot.

Admittedly, some of the people who use OSM around me use it because at a certain moment I've explained them the advantages. (I live in Europe and people frequently use other modes of transport besides the car, so OSM is legit frequently the better choice.)