Many times when I call a provider I haven't seen before, she does not answer and I leave a brief discreet message and say feel free to leave a message if I don't answer. Then I see in checking my cell phone that she calls back but does not leave a message.  Is this common? Why does she not leave a message when I say she can?

Too often a message left on a voice mail goes where it should not; thus they are careful about that.

This is one reason why email has become much more popular.

My guess is there is too much risk...  YOU might be LE.  Your SO might get the message despite what you say.

They are hearing several messages from potential clients when they check VM, not just yours.  It's much easier for them to simply never leave a message than it is to try and remember who said they could and who said they couldn't.

What if your wife checked your voicemails?  A good provider will never leave a message.