I try to assign a settler a job that's on the roof of the red rocket but they don't go up the stairs. They just stand there. Suggestions?

Obligatory "it just works"

Not sure if you are old enough but the settlement building reminds me of that game Lemmings. You had to create a clear path or they would kill themselves. Fallout 4 is the same way... You have to funnel them into a place that isn't hard to reach or they bug out.

I have had success with hangmans alley so far, the other settlements haven't worked so well. I built a massive water fortress on the island in fallout 4 and all my settlers swim away and peruse the middle of the island randomly instead of working.

I had a hunch they would not use the roof of the red rocket when I built up there... Oh well I'll just leave the beds where they are and they can stand around and wander all night.