Automation

I am finding when I run this portion of PowerCLI:

The output looks like this:

So the output of the commandlet getting the ESXiShelIInteractiveTimeout value is being added into the table after the write-host commandlet that follows it. I have occasionally seen the output of all three commandlets joined together in the third table at the bottom. 

Why does this happen and how do I prevent it?

You are confusing the PS output engine by doing Select-Object with different properties.
You can reset the output engine by doing a Out-Default after each Select-Object.

Super! LucD. That has helped. It sorted out some output from further down the code as well.

Why does the PS output engine get confused? 

It uses the 1st Select-Object and assumes that all your following Select-Object cmdlets will have the same number of properties.
And it combines those 2 together, as you noticed.
With Out-Default you ask in fact for a reset, and the output engine forgets everything it has "seen" before.

OK, that sounds like a deliberate design feature and quite useful. I don't know why I haven't discovered this before.

Thanks for the help.