Artificial pollination
Three agents carry pollen without being asked. There is a fourth that has to be paid: us.
Artificial pollination
The process of artificially depositing, on the stigma of some flower, the pollen of that same flower or of another flower of that same species, is called artificial pollination.
This can be done by hand or with the help of something like a brush.
Examples — Anthurium, passion fruit.
Figure to be added
Why a grower would bother
Natural pollination leaves two things to chance: whether it happens, and which plant the pollen came from. Pollinating by hand settles both. A grower can guarantee a crop where insects are scarce, and can choose exactly which two plants are crossed — which is how new varieties are bred deliberately rather than waited for.