I love OSM because there was an island in the middle of the river in my town and depending on the water height this island gets smaller and bigger, whenever there is a large amount of rain and the river is extremely high the island vanishes. Usually the island disappears from OSM within about 10 minutes and then is re-added when the river drops down to its normal level. Truly Wikipedia levels of pedantic pettiness, and I'm here for it.

Using ordnance survey maps is often like navigating a minefield. The ordinance survey maps are pretty helpful though.

I use comaps which is offline open street maps, generally better but can still be lacking.

Nothing is ever perfect and the quality also depends how active the OSM community is. In general Komoot is the common person's way to access OSM data.

OSM's reliability is very locational. I seem to be the only one that updates my area, which works out well as I have access to where future roads will be, (and I need them on the map for my job) but man. Construction here is crazy and a little assistance would be nice! At least OSM actually accepts my edits and additions, though. Google denies every single one, thus continuing the legacy of shit mapping by them.