Look at the edge straight on, with bright light and a loupe. Move it side to side a bit. If your bevel is clean the apex should be a thin dark line, no sparklies or random shiny spots.
I guess theoretically it could fail if you somehow managed to hone very consistently but not all the way to the apex (say, if you were resetting a bevel that had previously been honed with tape, without tape). So you'd end up with an apex with no burrs but that was too wide to cut effectively. But that sort of thing should be obvious if you use a sharpie to paint the bevel, or even just looking at the bevel with a loupe and noting where the scratch pattern changes.
I use a led Mag-lite and the naked eye. Shine the light at the edge and observe for reflection of light.
When no light is reflected your edge is sharp. I also verify with the TPT (thumb pad test) and three finger test for edge sharpness.