Anytime you run into problems it's time to start troubleshooting to try to find the root cause. For example next time you buff the good and use more than one product with a rotary buffer, use a side-to-side pattern for one product and then use a front-to-back pattern for the next product, then when you inspect the results you can see which product left the swirls if there are swirls present in the finish.
The goal is the second step product is supposed to remove any trace of swirls left by the first product but if the first product is a real aggressive compound then there's always a chance the second step process isn't aggressive enough to remove them all. Using two different directions for your testing will tell you which product is leaving the swirls.
In a perfect world the second step product is matched to the first step product in that it's is intentionally formulated to effectively remove any swirls instilled by the first step product. This assumes you're using products from the same manufacture.
I'm a big believer in using a system approach just to maintain a
Synergistic Chemical Compatibility
That is the chemist best knows how to make all the follow-up products in a system because they formulated the initial use or first step products in the system.
If that makes sense?
As someone else pointed out it's not a good idea to use multiple products on a single pad as it contaminates the pad and makes troubleshooting all but impossible.
Wool fiber pads are almost always going to leave swirls in the paint when examined in bright sunlight or using something like a Cruel Master, (Brinkman Xenon), as each individual fiber can instill it's own cut into the paint. Thus finish polishing should always be done using a foam pad.
One more note, and this isn't targeted at the OP, just a general comment about testing products, even on a hood from the salvage yard, when testing products limit your initial test to just sections of the hood until you find a combination that's working for you as it saves time, preserves the paint on the rest of the car, (or the test hood), and gives you a canvas to test other product combinations without the influence of other products.
