Most positive reviews are posted soon after they received their hot tub.  That’s going to be during the peak of their excitement, before they notice anything wrong. Oftentimes, the vendor asks the client to please post a review during this “honeymoon phase”.

However, the most accurate reviews would be at least two years later because by then, the hot tub will be showing its true colours, and it’s when the consumer is most aware of any problems and annoyances.  

The true sign of a good product is when the buyer is still happy five years down the road, not when it’s fresh out of the package.  But very few people hold off for that long before leaving a review. By then, enough time has passed that it doesn’t even occur to them.