Also, the OV-chipkaart is great - you can use the same card on trains, trams, buses and underground across the Netherlands.
I didn't travel much until a few years ago, but since then I've come to learn that the Dutch railways is probably the best I've seen yet (which doesn't necessarily mean it's the best as I can't compare all systems, but certainly seems among the best).
UK trains tend to have better service though: more power sockets (although I assume it's more common in NL too now? Haven't been in 4 years), and better catering. There's almost always coffee, and some trains even have a bar with beer/wine at comparatively reasonable prices.
Where I'm currently living in New Zealand doesn't even have a train connection, even though it sports a famous railway station :-(
[1]: See my confusion here: https://travel.stackexchange.com/q/37196/20608
If you use them occasionally you think they are amazing and much better than most other networks but if you rely on them everyday then you quickly realize how bad they are. Lots of random delays and unpredictable behaviors. Smallest change in weather causes disruption. And they are actually expensive even in comparison. (I cannot find the EU report that showed that, I’ll update the comment with it)
Also there is so little space for luggage or prams.