No soft shadows after rebuilding the scene

I don’t understand how shadows work with static meshes. I have this problem in general with UE and lights. But here’s a specific example of a problem I’ve been struggling with for hours.

I have a point light in the scene. The light spreads softly over the mesh as I adjust the parameters such as intensity, radius etc.

Then I hit the Build button. And the light and shadow looks completely different.

I’ve been trying to increase the Lightmass resolution on the mesh. There’s no real difference between a resolution value of 32 or 4096. At least not in terms of soft shadows or the smooth spreading of light. I’m currently using Raytraced Distance Shadows. Which is what was used in my pictures here. That didn’t make any difference at all. As you can see.