First logic is to reduce driver from choosing destination, but don't want hide destination like Uber because of the past experience of calling and ask.

Second logic is to match the ride and try to reduce incentive payment indirect way, imagine u strike a big job on 7.50 mark after completed 2 job, incentive payout straight away reduce or become zero, winner is grab because they earn the commission from u.

third logic is try to increase the matching rate, statistic nicely done > boss happy > KPI achieve. Customer complain no car, now with this system i match for u liao, but customer need to wait 20-30mins because is a b2b job

Not necessarily nearest one nowadays, u can order in front of me and the job could be assign to driver few km away. That is grab system for u for the reason i stated on the above.

Another reason is fraud prevention, last time some driver used to make fake booking to cheat incentive, now with this system is quite hard to cheat anymore, another one is to counter the modded apps.