Read the back of a lifted flake
The floor tells you what went wrong. Clean grey concrete on the underside means the bond failed at the slab, which is a preparation problem. White chalky residue and a domed shape means moisture pressure from below. A perfect tread pattern means hot tire pickup. Brittle paper-thin flakes that crumble mean a low-solids product.
Preparation failures
This is the most common by a wide margin. Resin needs a mechanically opened profile to key into. Acid etching, pressure washing and chemical prep do not produce one, so the coating bonds to the closed surface film rather than the concrete, and lifts in large clean sheets when anything stresses it.
Moisture failures
A slab on grade without a working vapour barrier moves water vapour upward continuously. Seal that under an impermeable film and pressure builds until it pushes the coating off, typically in year two, in domed bubbles with efflorescence underneath. A calcium chloride or in-situ RH test before quoting predicts this entirely.
What fixing it involves
Failed coatings have to come off completely, grinding for thin or already-lifting films, shot blasting for thick or well-bonded ones. Coating over a partial failure guarantees the new floor fails along the same lines. Removal typically adds $1-$3 per square foot, which is why doing it correctly the first time is the cheaper route.
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Free site visit with a moisture reading, then a written fixed price. Across the BC Interior.