Once but never again! / One time only! [Dutch phrase of the week]
Literally “One time, never again” this informal expression implies that the experience was bad or disappointing and you have no intention to go through that again voluntarily. Therefore it is a bit stronger than just a ‘one time affair’.
You will also hear the (more formal) expression “Eens, maar nooit weer”, which has the same meaning.
– “Ik ben vanochtend met de tram naar het werk gegaan. Eén keer nooit meer, wat een plebs!”
(“I took the tram to work this morning. Never again I say, what plebs!”)
– “Ik heb laatst meegedaan aan speed-daten. Nou, één keer nooit meer, want dat werkt dus echt niet!”
(“I have recently participated in speed dating. Well that was a one time affair, because it really doesn’t work!”)
– “En ben je nog koffie wezen drinken in the Amsterdam American Hotel?” – “Ja, en het was één keer nooit meer, wat een afzetters!”
(“And, did you have coffee in the Amsterdam American Hotel?” – “Yes and I will never go back, what a rip-off!” Mind that “afzetten” is the verb for “serious overcharging” for something (goods or service). The use of the verb “wezen” indicates an activity (a longer period of time).)