I never dive under turret early game. And I mean, never. For me to decide to dive I have to be extremely fed compared to the enemy.
I usually am happy to just push my enemy out of lane, but sometimes it seems to me I could kill them and get a better advantage. My biggest counter when me and the enemy are even (or I am slightly ahead) is them sitting under turret.
I have this issue when I jungle too. Sometimes I could have free kills in early game but I am just not confident enough to dive. Other than champion skills (like roots, stuns, dashes that could kill me if I dive) and HP what should I consider before diving someone?