Why do my Objects disappear when I click on them

I’m noticing in some of my more complex models that when I click on a particular object it disappears. When I click off of it, it reappears. I’m trying to select the faces to apply some materials but once I engage the object I can’t see it, so no ability to apply materials.

What’s happening here?

hello, does it disappear when you enter a group ?
sounds like clipping

see this