Sellers cluster at two extremes: everything on one marketplace (usually the first one they tried), or listed everywhere an app can cross-post. Both cost money in ways that don't show up until they do.
A single channel is a single point of failure — one algorithm change, fee rise, or account review away from zero income. Less obviously, it's a single source of information: with one channel you know your sales, but you don't know your relative sales. The maker who discovers her candles sell twice as fast on Folksy as Etsy at the same price learned something worth actual money, and she could only learn it by being in two rooms at once.
Every channel is stock reconciliation (selling the same one-off item twice is a genuinely bad afternoon), separate messages, separate reviews to maintain, separate fee models to price for, and separate "why did this platform hide my listing" mysteries. Cross-listing tools ease the mechanics, not the attention. Beyond two or three channels, most small sellers are spreading effort thinner than the extra sales repay — breadth costing depth.
Pick your primary from where your product's discovery style lives (that's what the picker is for), and add one secondary chosen for being nearly free to maintain — Folksy for makers, eBay-private or Vinted for resellers. The secondary's job isn't matching the primary's sales; it's insurance, comparison data, and the occasional buyer the primary would never have shown you, all at pennies of cost. Give the primary your real effort — photography, keywords, the good descriptions — and let the secondary run on copies.
Add a channel when a product proves it travels (steady sales, repeatable photography, margin that survives the new channel's fees — check with the comparator), not because a listicle said the platform was hot. And retire channels honestly: a marketplace that's sold nothing in six months isn't a channel, it's a tab you feel guilty about.
General guidance, August 2026. CAAC.