For me, as a newcomer, after birding a bit over the years and then now becoming interested in being more "pan-species". I was very excited to start photographing insects in the UK. I can go back to a spot 50 metres from me and regularly find new species of insect. This doesn't happen with botany. Shooting static species is less fun!
I have also been using this site for identification before recording on iRecord. iRecord seems to have more active experts in invertebrates than anything else in my home county. This gives me added incentive to shoot them.
I also read that invertebrates are under-recorded in general, so feel like I am contributing more by recording them.
I wonder what the balance is for iNaturalist. I have also started using that as I am abroad in my other home country at the moment. In this country at least, insect identification is very inactive and its much easier to ID botany, so I am uploading more botany there...