If the dining table doesn’t fit, though, you might not be able to get it through the front door. Returning that large object is a complicated (and sometimes costly) proposition. How do you even repackage a table? Assuming you get it through the door, you may just have to live with it, or sell it to someone else on a site like Craigslist, the place where our shopping mistakes go to die.

As I sat at my computer, sifting through images of sconces, I filtered the vast collection by style, an option that sent me hurtling toward an identity crisis. Was my style “industrial” or “glam?” Or maybe it was “coastal” or “global inspired,” two categories that made me wonder why a sconce can’t be both coastal and globally inspired.

What if I was none of these categories? What if the light fixture waiting for me at the end of this search really belonged in the rather bland “traditional” category that I had just filtered out?

“There are too many choices. Where do you start?” said Jill Vegas, the author of “Speed Decorating.” Scour the web long enough and “it can just spiral into questions about yourself. Is this the life I want to be living? Is this what I value?”

Even the most diligent shoppers can be led astray. Brigette Parsons, who lives near Gainesville, Fla., thought she had done her homework when she bought a headboard on Wayfair in 2014 for the master bedroom she shares with her husband, Steve Parsons, 40, a state police officer. She had spent hours scouring the internet, reading through dozens of customer reviews.

But there’s an art to reading online reviews, the crowdsourced equivalent of asking everyone in the mall: What do you think of that dress in the window? Is the fawning praise really deserved? Is that lone critic a soothsayer or just a crank?