You can limit how many jobs a driver can do at any given time.
This is good if you don't want a driver doing too many food deliveries at once or you want to restrict a taxi or car to only take 1 booking at a time.
Uber limit their drivers to certain capacity based on what the driver can do
- UberX can only do 1 job at a time
- UberRush can only do 1 job at a time
- UberPool can do 2 jobs at any given time because it is a pick up / drop off like service
To restrict your whole driver fleet capacity, go here
Alternatively if different drivers have different capacity e.g. biker vs truck you can go to your merchant map or manage driver page and update each individual's carrying capacity so they can't see or accept jobs when they are busy and at full capacity