[kazinator]

Slovak proverb: "ponáhľaj sa pomaly" -- Be not hasty, when you hurry.

[titanomachy]

English has "more haste, less speed" which I think carries the same message.

[kazinator]

What I don't understand is why the most literal translation into English, which is equally succinct, doesn't "work" somehow. Namely the translation: "hurry slowly".

It's just so awkward. Yet the grammar isn't bad; there is nothing wrong with "walk slowly" or "eat slowly".

"Ponáhľaj sa pomaly" is perfectly euphonic to the Slovak ear, while "hurry slowly" seems clumsy somehow. We need to make it more sophisticated somehow, like "make slow haste", or "slow haste makes faster" or whatever.

What is the reason ...

I suppose; if everyone said "hurry slowly!" it might wear into usage.

[adamtj]

I'm told that the US military uses the phrase "Slow is smooth, smooth is fast."

[schoen]

It also exists in classical Latin and Greek:

https://en.wikipedia.org/wiki/Festina_lente

[gandalfu]

Spanish: visteme despacio que tengo prisa

Or: visteme despacio que ando apurado

[mixedCase]

Or, in more rioplatense fashion: "Si corrés te cagás en los pantalones"