system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do liquor bottles sometimes have those thing that make it pour really slow?
gpt
They are to measure the fluid.

Barkeepers need to measure a lot of fluid in as short of an amount of time as possible.

I don't know the exact figure, but they pour at around 1cl per second, so if the drink asks for 2 cl you pour for 2s. That is much more accurate than having an open bottle and just guessing how much you pour.