"Here's a question for you or anyone else here - how many people buy a product and then go online to post review, good or bad?"
Last time I looked into this I found it to be 1%.
This one shows considerably less...
"It depends on the type of a product or service they review and how aggressively companies stimulate their customers to do it. Foe example, only .6% (ave) of consumer electronics purchasers reviewed products they bought in 2013. This estimate comes from aggregating customer reviews of their experience with specific products and dividing the results by the number of these products sold during that year. While the online reviews are publicly available, the number of units sold is usually available only as an estimate from a 3rd party. See example here 3 simple ideas for engaging your customers to sell your products
While the percentage of reviewers is undeniably low it is important to remember that percentage of customers surveyed (and responded) is often considerably lower than an example above.
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