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.)
Personally, I exercise the “growth mentality” here. Meaning, I don’t compare with a target value such as “I’ve converted 10% of the Earth population to OSM”. Instead, I compare with OSM as it was 6 months ago. This approach gives peace of mind and steady progress for me personally.