I am guessing that delays are not 5J specific, but across all low-cost airlines in general. When you only have 45 minutes at an outport, expect to offload passengers and luggage, and then board a new set of passengers and their bags, any hiccup (say traffic jam at the airport) can trigger a chain reaction to major delays to the end of the day.

I got delayed in HKG for 1 hour and 30 minutes - the aircraft was late by 1 hour coming in from Cebu, and the uncles from Jardine Aviation Services took forever to load the cargo - all the passengers were sitting on the aircraft for 30 minutes before all the cargo got loaded !