What do you think the rules for a 1v1 custom are?

so i like to take people up on there "1v1 me bro" post chat rage but ive noticed that there's usually different opinions on how a 1v1 should be played. Ive always played as its first blood or first tower, but some people think its till the nexus is over. your thoughts?

also the reason i only want to play till first blood or tower is because i dont want t waste a full 20 minutes or more on a game that's simply about who is better at a 1v1 if i beat you in lane/solo killed you why would we keep playing also the longer a game goes the more you have to take into account things like scaling of each champ a hyper carry will eventually win if you drag the game out long enough and the point is to See who has better lane mechanics not who can pick a hyper carry and stall for a long time