Refills, and the concentrate problem

Why it suits refills

The dispenser is the expensive part and it lasts, while the contents are cheap and thin. Selling a pump once and the liquid repeatedly is a sensible shape, and customers in this category are receptive to it.

Concentrate moves the dilution to the customer

Shipping a small bottle of concentrate and asking the buyer to add water removes most of the freight and most of the packaging. It also hands them a step they can get wrong, and the foamer is unforgiving about exactly that step.

Which is the tension

Too concentrated and the pump clogs or will not foam; too dilute and it does not clean and the preservation is weakened. A product that depends on a customer measuring correctly has a failure mode built into the business model.

Make the measurement hard to get wrong

A fill line on the bottle, a concentrate dose that matches a whole sachet or a whole small bottle, and an instruction with no arithmetic in it. Anything that requires somebody to measure a fraction will be approximated.

Preservation has to survive the dilution

Adding tap water at home changes the system the preservative was designed for, and the product then sits in a warm bathroom for weeks. The preservation has to be adequate for the diluted product under those conditions, not for the concentrate in the bottle.

Say what water to use

And whether it matters. If the product tolerates ordinary tap water, say so plainly, because a customer who is unsure will either not buy the refill or will worry about it every time.

Price the refill so it is obviously worth buying

If the saving is small, customers buy the new bottle instead and the proposition quietly fails. The refill has to be visibly cheaper per wash or the whole scheme is packaging you paid to develop and nobody uses.

References