/reload a reloads the admin informations ( common -> gmlist ) , it does not update the prototype tables ( such as skill / item-mob_proto / etc )
/reload q reloads the quest table,which contains every single quest of a player, a server that have 100 players and biologist quest (30-94) [ 100 players above 30 or between 30-{maxlevel} ] will reload at least 300 lines for the 30 quest. If you didn't understand, let me explain it more clearly:
A player that finished the biologist (30-94) {30,40,50,60,70,80,85,90,92,94} (10) will generate 60 lines in quest and 10 lines in affect.
A server with 1000 players that completed the biologist will have over 6000 lines, there you have to add any box quest / any message quest or w/e.
Conclusion: Never use /reload q. You can use reload prototype if you have a powerful dedicated server with high CPU and high internet speed or not to many players online.