The Great Wall of China has more than 9,000 Google reviews, with an average of 4.2 stars. Not bad for one of the most astonishing achievements in human history.

But you can’t please everyone.

“Not very tall. Or big. Just sayin. I kinda liked it. Sort of,” wrote one ambivalent visitor of the structure, which stretches thousands of miles . Another complained, “I don’t see the hype in this place it’s really run down and old … why wouldn’t you update something like this? No USB plug ins or outlets anywhere.” Someone else announced that he’s “Not a wall guy. Laaaaaaaaammme.”

Even Shakespeare can’t escape the wrath of consumer scorn. One reviewer on Amazon awarded Hamlet just two stars: “Whoever said Shakespeare was a genius lied. Unless genius is just code word for boring, then they’re spot on. Watch the movie version so you only waste two hours versus 20.”

It’s no wonder why we live and buy by online reviews: The Washington Post recently reported that a third of American adults use a computer or phone to buy something at least once a week — “about as often as we take out the trash.” Last December, 75 percent of Americans said they would do “most of their holiday shopping on Amazon,” according to CNBC’s “All-America Economic Survey.”