Factorio is about the automation of production lines and logistics puzzles, and it does it amazingly well. If you enjoy those mechanics then it's going to be easy to lose a lot of hours to this. I personally think it's easy to pick up, but it's one of the deepest games I've ever played and it can take hundreds of hours to get really good at. It's extremely satisfying to automate the production of something complicated. The tools it gives you to manage these puzzles are really well designed, mechancically, and the gameplay loop is really rewarding. It's spoiled me really - I've reached almost 500 hours in this now and it makes all other games feel shallow and short in comparison.