"There must be a better way to do this." I thought, staring at the 5th Edition D&D rules for XP and Levels. 

I'd always shunted XP, in favour of simply telling my players when to level. But it seemed arbitrary, it felt like I was being unfair on my players, since I had total control over the pace of leveling. All the while, they had no tangible sense of progression.

It felt like a waste, there was this entire system of leveling and the way to decide when it happens added nothing to the game. Players either had a fixed idea, or no idea of what took them closer to a level. Neither of these options related to what made the game good, I didn't want my party blitzing through challenges or picking every fight just because they knew it was the only way to level.

Fundamentally, I felt a core design issue was present in 5th Edition. Even with milestone, the rules still suggest preparing what gives XP ahead of time, as if you have a crystal ball to see what will have impact and meaning. This entirely shunts away organic emergent gameplay which is where tabletop games absolutely shine. It assigns meaning on things before they happen, which is impossible.

So... Why not make an XP system based around these moments? Focus on the high level ideas of what makes the game good, and push to get the whole table involved! Thus what would become Emergent Experience was born, one that was designed from the ground up to get players invested and involved, rather than alienating them!