> The manufacturer keeps working to improve the quality
Call me cynical, but I think it's naive to make this claim.
Manufacturers don't optimize quality, they optimize profits. Even if there's sufficient competition, manufacturers don't race upwards to improve quality, they race downwards to reduce the cost and undercut the competition.
You can see this in kitchen appliances. People complain about how they don't last as long as they used to and are harder to repair. That's because when a customer sees a $30 blender and a $50 blender on the shelf, they will nearly always pick the $30 blender, even if the $50 blender is a higher quality. There was a race to the bottom on pricing, and corners had to be cut.