Two thirds of reviews left online are negative, a study has found.
A survey of 2,000 adults, who leave comments on social media or websites about a business, product or experience, found they leave an average of 36 reviews-a-year - or three a month.
But on average, 24 of those will be negative.
More than four in 10 (41%) leave unfavourable comments to warn others of bad service, while 15% claim they feel awkward if they leave anything which is too glowing.
And 18% simply forget about it if they have nothing to complain about.
Hygiene and cleanliness are high on the list for many people, with 32% saying they wouldn't return if a company’s hygiene wasn’t up to scratch on the first trip.
The research, commissioned by cleaning experts P&G Professional, also revealed hotels and restaurants, (50%), shops (35%) and pubs (25%) are the places people left the most reviews.
Restaurant critic, Grace Dent, said: “As the adage goes, you only get one chance to make a good first impression - and in today’s climate, the stakes have never been higher for hospitality businesses.
“As this research shows, online reviews can make or break a business, which is why hospitality venues have to pull out all the stops to guarantee a five-star experience.
"The food must be outstanding, the service needs to be stellar and the environment has to be spotless.”
The study also found one in 20 adults, who leave bad reviews, admitted they do so in the hope of picking up a freebie or money off a future purchase.
And 66% also feel businesses have to take on board customer service reviews in order to improve their service and learn from their mistakes.
But 41% are happy to take the word of a stranger posting an online review, with 53% also more likely to trust customer comments than star ratings assigned to hotels.
Showing how important a good first impression is, 40 percent of those polled, via OnePoll, would never revisit a venue they’d previously left a bad review for.
Of those, 33% don’t believe businesses deserve a second chance after messing up once, and 32% would never return if a company’s hygiene wasn’t up to scratch on the first trip.
A spokesperson for P&G Professional said: "Reviews are more important now than ever with the current economic landscape creating challenges for hospitality businesses, and leaving positive reviews can help support local businesses.
“Particularly when it comes to restaurants, pubs and other hospitality venues, cleanliness is a huge driver in getting a good review rather than a bad one.
"So, for any new businesses in this area, keeping things clean can offer an early, easy win for getting off on the right foot with new customers.”