You can't layer wax. One layer does not lay or rest upon the next instead you remove and replace one with the other.
Solvents are used to liquify "wax" and in general wax is just an oil that lays on top of the paint. There is no bonding, no cross linking with the painted surface. Wax is just a beauty enhancer and last tops maybe a month. In high heat and humidity 2 or 3 weeks. Heat will start a quick evaporation of wax, no matter what wax it is. There is no such thing as "100% carnauba wax, with natural UV inhibitors enhanced with banana oils to feed your paint!"
I disagree with some of this. But, first we have to define what "wax" is. I'm assuming we are talking about non-hybrid (no sealant) component type waxes like Souverän, P21S, Zymöl Glasur, etc... ?
While I agree wax just "sits there", I think saying wax last "tops maybe a month" is selling it short a bit. In fact, unless the vehicle was exposed to salt, sludge or excessive rain - I can't see any decent wax lasting only a month IME.
Of course, a lot of modern waxes have hybrid designs that include a sealant component. Many of these products can last several months.
I will admit "feeding paint" is bunk. I think the "100% carnauba" thing is just a bit of slick marketing... As you know, they are not saying the contents in the wax pot are 100% carnauba, but that ALL the wax ingredient that was used to formulate the product was carnauba; opposed to bee's wax, montan wax, etc...
Just because your paint beads water does not mean the presence of wax because if you spray water on a freshly painted fender panel it will bead like it's got wax all over it, due to surface tension but not any wax.
I agree this is true - but a bit unclear possibly. Most people aren't working on a freshly painted panel - they are working on a car that lives a life on the road. Therefore, the paint is not "brand new".
So, while beading isn't indicative of a wax layer per se, the "freshly painted panel" idea only is relevant if your working on a freshly painted car - which isn't the norm. Most of us have seen non freshly painted cars not beading in the rain or while being washed. Also, to the more experienced of us - we have probably noticed wax beads tend to look different than just the beading of fresh healthy paint.
However, all (100%) of the cars will bead if they are prepped and waxed correctly. If the wax is not re-applied, they will no longer bead after a while. So, therefore - IMHO, beading is *some* indicator wax is present on the average car.
Wax also does not bring about gloss or depth of paint. That's what a highly polished surface does or creates. Wax gives a boost or enhances that gloss by a small margin only. Take some Pledge furniture polish and spray your car down, step back and see how it looks compared to your favorite wax.
This is the idea that I think some newer people get confused on. It's common for a pro (like Anthony) to mention something like "wax doesn't bring about gloss or depth" - polishing does. I agree that a waxed surface full of defects will not look good, regardless of the wax product.
However, wax can enhance paint - even freshly polished paint. I think some of the "all wax is the same" crowd think because wax isn't the way to getting the highest improvement in paint appearance (polishing is), that means wax can't affect the appearance of paint at all. Which I do not agree with.
Yes, it's true wax can't "fix" bad paint. But that doesn't mean it can't enhance good paint.