I've played Factorio now for a couple of hours (like 50 or something) so I haven't seen everything yet. But you develop those faster transport belts very early and I still only use the slowest ones.
Mathematically it doesn't make any difference for transporting stuff which belt is use: If I put an item let's say every 2 seconds onto the belt at the beginning then there will be an item at the end every 2 seconds, too, no matter how fast the belts are. Only the time for the first one to arrive at the end will differ with different speeds. But once the "flow" is working it doesn't matter anymore. I've already thought of density reasons but it still seems not very relevant.
So I just wonder what practical use they have (apart from mechanics like using belts to move more quickly through the world or using belts as a defense etc., I'm talking about just logistic mechanics). As said, I haven't seen/developed everything yet but I still couldn't come up with a sensible practical use of faster belts.
That's just something that bugs me so I thought I just ask some experts here!
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