Just posting this response I gave in another discussion about tweezing in the Brazilian area.  There are always questions on it so I wanted to make sure that those that wanted answers could see them. 

I never tweeze.

Why not?

1. It's more painful for the client

2. It's set the expectation that EVERY hair will be removed and that is just not possible.  There are going to be hairs that get left behind, mostly because the technician can't see them because of poor lighting.  And some hairs will break. 

What do I do?

1. Educate the client, especially those that have been shaving, that some hair may no be long enough to grab today, so we will get it next time. DO NOT have them shave or tweeze themselves.  Most people tweeze incorrectly anyway and end up breaking the hair rather then removing it and then you will be right back where you started.

2. If you are using hard wax you can go over an area and pick up strays with the wax instead of tweezing

Of course you never want to leave big patches of hair that you can obviously get, but for one or two hairs, if you cannot go back and pick them up with your hard wax, then instruct your client to leave them till next time.  Telling your client to shave or tweeze takes away from what they are trying to achieve.  They want to wax to stay smoother longer, if they are shaving that is never going to happen and they will be dissatisfied with your work.