The game concept I like the most is the Special Events system, which allows multiple tactical options that are almost equal in strength. In general I think the Youth Academy is the best feature in the game as it creates a close connection to your own players.
One of the best parts of Hattrick, for me, is the fact that you can somehow massively relate to a bunch of fictional players with fictional names and treat them like they're real world players.
My best Hattrick memory was when the city where I lived (L'Aquila, Italy) was hit by an earthquake. I received a lot of support, a lot of help, a lot of love. It was a very hard time and Hattrick was there, with its community, with me. I will never forget that.
What I like about the Hattrick community is that there are real people and you don't just compete against the computers. You play against each other, but you can also help each other in the forum and talk about everything.
When I registered, I liked that Hattrick has fantasy names instead of real players. That got me hooked. I also liked that all opponents were people of flesh and blood… and also that they turned out to be really helpful, showing me the steps you need to take as a new user to improve your team. Today, I am a good mentor myself.
I started playing Hattrick because some of my co-workers absolutely wanted to introduce me to Hattrick. When I finally tried, it was the Valentine's Day of 2009 … and I am still here, ten years later!