I have found that this is common with french lace.

I would guess that it has to do with the larger hole pattern (less surface area for the tape to grab) and the fact that it is made of nylon which in and of itself makes it resist sticking.

I'll bet the factories could develop a way to "rough up" the underside of the lace prior to ventilating that would create a surface that isn't quite as smooth that would give the tape something to grab on to. I would even try using a little fine sandpaper on the underside, but with hair tied into it it would be destroyed. Even if you could do that you might end up with a glue buildup problem....

I don't have a problem once the unit is on my head, but it can be tricky to remove the tape backing and keep the tape sticking to the unit as you are attaching if you are applying it to the lace first. One thing you can try is adding a little extra "stick" to the tape by applying some glue to the tape before putting the tape in the unit. That also helps knock down the shine if you do it the right way.