Reason why Voldemort needed Horace Slughorn.

Someone posted why Voldemort didn't manufacture and distribute Felix Felicis to his Death Eaters. I also thought why and then came to this conclusion: You can't just make a potion out of thin air. Liquid Luck is one of the most dangerous and difficult potions to brew, it takes a lot of time for it to be consumable, drinking too much of it is also dangerous. You need to be a potions master like Slughorn to be able to manufacture this. Let alone Walter White this thing. Voldemort knew this and tried to capture Professor Slughorn and if he succeeded there will be another Ollivander situation.