Gloss is a mirror, in both directions
A high-gloss floor reflects light back into the room, which is genuinely useful in a basement or a shop, and it makes a metallic or a deep colour look its best because you see into the film rather than off it. It also reflects the ceiling, the lighting and every undulation in the slab underneath. On a floor that is not exceptionally flat, raking light across a gloss finish picks out every trowel line and patch.
Satin is the practical default
A satin or low-sheen topcoat scatters light rather than reflecting it, which hides scuffing, burnishing from foot traffic, and small imperfections that a gloss would advertise. In a working garage, a shop or a commercial floor it looks better for longer with less effort. It is also the right call for anywhere glare is an issue, which includes most retail and any space where people work under bright overhead lighting.
Dark floors especially
On a near-black floor, gloss maximises every problem: dust is visible, footprints are visible, and burnish patterns from traffic show as patches of different sheen. Satin keeps the depth of the colour and removes most of that. We will usually recommend satin on a dark solid colour or a dark metallic unless the room is a showpiece with a cleaning routine to match.
It is a topcoat choice, so it can change
Sheen lives in the final topcoat, which means it is the one decision on a floor that is genuinely reversible later. A gloss floor can be abraded and finished in satin, or the reverse, without touching the decorative layer underneath. It is a one day job on a garage. That makes it a lower-stakes decision than colour, and worth deciding by looking at a sample panel in the actual room rather than agonising over.
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