Without a Traceroute

One of the strangest things to me about Dutch toilets is that they all have both a ‘big’ flush and a ‘small’ flush. I think the idea is that you use small for #1 and big for #2 and save water that way. To me, it adds unnecessary decision-making to the bathroom process.
This is a flush mechanism from the early 20th century, and they already had two different flush sizes.