I've lived in Dublin for two and a half years years. I like to tell about its public transport to people who complain they have it bad in their city (not that it's an excuse, it's just extremely entertaining to see their reaction):
- There's one suburban train service (DART) that kinda goes through the centre and then just takes you to suburbs. It's like an S-Bahn except it doesn't stop anywhere useful in the city itself. Unless you live in one of the expensive suburbs it takes you to, you can basically forget about it. I've only used it to get out of the city for hikes.
- There's two tram lines, that until a year ago didn't even cross. Oh, and the trams are _extremely_ slow because they have barely any dedicated lanes in the centre, instead sharing the street with the rest of the road traffic. Even when they are on dedicated tracks, they're still absurdly slow for some reason (in comparison to all other tram systems I've used elsewhere).
- There's buses. They're ugly, loud and extremely uncomfortable. They have no timetable, instead they leave their terminus at some fixed time and then go as fast or as slow as they can, sometimes skipping stops if the traffic is bad. [1] Since this means you basically cannot make distributed, reliable connections between buses, they maximize their usefulness by running most of them through a single choke point in the city centre, where it can take up to 30 minutes to go through. Each line has a ton of stops, and every time passengers get on the bus, they go single-file through the driver that asks for the target stop and charges their pre-paid card accordingly (or you can go through a separate card reader that just charges you a daily flat rate, but that doesn't make sense if you're not commuting a long distance that day).
And that's it. Nothing else. Unless you're lucky enough to be on the _two_ tram lines or _one_ commuter train, you're stuck with shitty, expensive buses. Don't move to Dublin.
[1] - There is real-time bus tracking, but this doesn't help you to make a connection, just to leave home/work and not have to stand in the rain for too long. Just hope you bus doesn't get stuck in traffic along the way.