When you treat a pair of leather shoes they usually turn a little darker. The same thing happens when you wax G-1000 fabric. A waxed garment has a slightly darker nuance than an unwaxed garment. The difference is more noticeable for some colours, for example yellow, but can hardly be seen on other colours.
All textiles have some fibres on the surface that have been pulled away from the threads. You can see this clearly on a pair of well-worn jeans, for example. The number of fibres “sticking up” from the fabric increases the longer you use the garment. When you wax G-1000, the wax binds these fibres together and the fabric looks darker. Since the wax is holding together the G-1000 fabric, it also becomes stronger and lasts longer.
Sometimes it can be difficult to apply the wax evenly from the block of wax. This can make the garment look striped after the wax has been melted into the fabric. But this is nothing to worry about. You just need to apply and melt in a new layer of wax to make the stripes disappear.