For myself, I create these scenes based on vulnerability. A lot of my stories involve whether someone's efforts have been in vain or not in vain: bonus points when it's a character that generally tries to keep up a strong appearance and not show their emotions. How that happens can depend on the situation:
The parental guardian who goes above and beyond for those they love -- especially in dire situations.
People who try to bottle up their feelings in order to "look strong", but you can tell it wears away at them.
Children who mourn but are confused about why they're mourning. The heart hurts, and they're scared because they don't know why and don't know how long it'll last.
When they make it, it hits the heart. Because at this point, we know how hard the character has worked: what they've given up and gained to get to this point. If it's done well, it's not completely self-sacrificing, but the character still has to make some tough decisions. Seeing them make it hits my heart and I tear up. Especially if they end up crying and haven't really cried throughout the story before -- because now? Now they're relieved. They can be vulnerable because everything is ok.
When they don't make it, it hurts. Because again -- we know how hard the character worked and what they went through. So seeing them NOT make it, despite that effort, breaks my heart. It hits a bit closer to reality, seeing this strong character -- who tried hard to stay strong -- finally shed those tears they tried to hide. I mourn for them.
For a scene to be emotional, you kinda have to work with things we don't really want to talk about sometimes. That sense of vulnerability with others and ourselves that feels accepted when we see it in media. When we see a character go through what we endure, regardless if they fail or succeed, it just invokes a sense of "you're not alone".
To write like that, you have to work with understanding what it means to be vulnerable. And that might mean diving into your own heart and seeing what lies there.