That is a great question to think about. For me, it is a mix of high-quality visuals and the feeling that a big win could happen at any moment. I have been playing at the PowerPlay online casino recently and I think they nailed that balance perfectly. The animations are so smooth and the sound effects really pull you into the action. It is a new online casino that clearly put a lot of work into the user experience. I find that I keep coming back because the gameplay is just so satisfying and responsive. When you combine great graphics with a fair chance to win, it becomes very hard to stop playing.