Founders can recite their average rating from memory and can’t name the last one-star review they personally answered. That gap is backwards, and it costs more brand equity than the bad review ever did on its own.
The five-star reply is a courtesy. The one-star reply is a demonstration.
Thanking a happy customer in public is nice. It confirms that good service happened once. It teaches a prospective customer nothing about what happens when service doesn’t go well - and that is the only question a prospective customer actually has, because they already assume most of the good reviews on the page are true.
A public complaint isn’t written for the complainer
By the time someone leaves a one-star review, they are rarely looking to be won back. But hundreds of undecided readers will see that review before they see anything else on the page, and they are reading the reply, not the complaint, to judge whether this is a company that handles things responsibly when things go wrong. The complainer is an audience of one who already left. Everyone still scrolling is the real audience.
What most replies get wrong
A copy-pasted apology with no specifics reads as exactly what it is - a template. A defensive reply that argues with the customer reads worse. The replies that work name what happened, state plainly what the company did or is doing about it, and stop. No line about taking feedback seriously. Just the fact and the fix, in a real voice, visible to everyone who scrolls past.
The habit worth building
Someone with the authority to commit to a fix - not necessarily the founder, but someone empowered to speak for the company - should read and answer every one and two-star review within a day, in public, on the platform it was left on. A private resolution with no public reply answers the complainer and ignores everyone else reading. The public page is the actual product; the private fix is customer service. Both matter, but only one of them is marketing.
The five-star reviews already did their job by existing. The one-star ones are still doing theirs, every time a new reader arrives and reads what happened next.