There are two easy ways a product becomes a commodity.

One is, by focusing on the price and using the price as the main criteria. That product only has the price to differentiate itself from its competition.

The other is happening by standing still and letting the competition run-up to your position. Whatever has been your differentiation factor in the past has been copied and used by the competition who learned from you and others. The price becomes what the competition now uses to pull you into the commodities market they created.