Penetration pricing is the opposite of skimming. Instead of starting high and drifting down, the brand launches at a price low enough to make the buying decision obvious, banks on switching costs or habit to keep customers, and raises prices once a base is established.
If switching costs are zero, penetration pricing just buys you a temporary spike in customers who will leave the moment the price goes up. Categories with frictionless competition (most e-commerce categories, frankly) do not reward the strategy because there is nothing to lock customers in once the introductory price ends.
Pure penetration pricing is rare in e-commerce because there is no real lock-in. What is more common is a tactical version: launching a new SKU at an aggressive price to win Buy Box position or build review velocity, then drifting prices upward once the listing has authority. This works because Amazon's algorithm rewards listings with sales history, not just current price.
Example: A new Amazon seller launches a kitchen tool at $19.99 against competitors at $24.99. The aggressive price drives volume, the listing accumulates 200 reviews in two months, and the seller raises the price to $23.99. The reviews and ranking carry the listing forward at the higher price.