One Drop 10-ball bearing

This isn’t just a OD 10ball thing; The majority of bearings out there will have some sort of break-in period as whatever little factory lube wears off and any minuscule imperfections on the balls smooth out. The “Play through it” method is a 50/50 shot. It can work, but if it doesn’t work or you just don’t want to bother with it then clean the bearing and it will play fine.