This is a really misguided opinion but possibly based on working with misguided managers. Velocity in traditional scrum-style agile is metric of product complet

This is a really misguided opinion but possibly based on working with misguided managers. Velocity in traditional scrum-style agile is metric of product completion. If you're doing point estimates or the like and you've sized your MVP at 128 points and you've completed 64 points with 180 developer-days then you are 50% done and can project completion in another 180 developer-days. That's what it's predictive of. Saying it doesn't explain why your velocity is your velocity is a big duh. It's not supposed to. It's the primary indicator of progress. If velocity is too slow then you go figure out why or what can be done. If you're on time or early, then great.