Every extra step between cart and paid order costs a slice of the order, and the slice compounds. I call it the checkout tax: the revenue that leaks out of a store purely because buying is annoying. Industry abandonment studies put roughly seven in ten carts unfinished, and every store I have audited leaves more money here than it spends on ads.
Where the money leaks
The usual offenders show up in the same order on almost every store. A forced account creation before payment. Shipping costs that appear only at the last step. Sixteen form fields where five would do. A coupon field sitting at the top of the summary, which sends a chunk of buyers off to hunt for codes, and some never come back. On one store I traced a full 8% of sessions leaving at the coupon field alone. Those buyers were ready to pay and went looking for a discount instead.
Phones add their own tax. A numeric keyboard that does not appear for a card field, an address box that fights autocomplete, a page that reloads and drops the form when the buyer switches apps to check an OTP. Half my traffic arrives on a phone and phones convert worse in checkout on every store I have logged. Every one of those fixes is unglamorous plumbing, and each one returns a fraction of a percent that never gives it back.
The fixes that paid for themselves
Guest checkout is the cheapest win I know. On a home goods store, switching it on took checkout completion from 58% to 71% in three weeks, with no other change and no drop in account signups. Flat shipping costs declared on the product page closed most of the rest of the shipping surprise. Address autocomplete cut average checkout time by about forty seconds on mobile. Adding Apple Pay and Google Pay turned phone checkout into a thumbprint for the buyers who use them, and they now carry a real share of orders on every store I run. Four changes, none of them clever, and the tax got roughly a third smaller.
One more habit earns its keep: I read the payment failure log monthly. Declined cards, expired cards, wallets that error out. On one store, a shipping rule was silently rejecting an entire country, and the log showed a week of doomed attempts before anyone noticed. A checkout that fails quietly collects the tax anyway, and the log is where the store confesses.
The pattern holds every time: friction removed today shows up in this week’s numbers. A clean checkout is the highest-return surface in the store, and it is also the one owners look at least.