A headline battery number is not a lie so much as a very carefully chosen truth. The trick is knowing which choice was made. There are only four, and once you can spot them the spec sheet stops being annoying.
Earbud runtimes are quoted at fifty per cent volume with noise cancelling off. Most people listen at sixty to seventy on a train with cancelling on. That is not a rounding error, it is routinely a third of the claim gone.
“30 hours” almost always means five in the buds and five more charges in the case. Useful, but it is not thirty hours of anything. We quote both figures separately and score against the bud figure.
The efficient codec gets the marketing runtime. If you use the one the maker spends a paragraph bragging about, expect ten to twenty per cent less.
Nobody publishes a runtime at 300 cycles, which is roughly a year of daily use. We cannot test that inside a three-week window either, so we do the next best thing and check whether the battery is replaceable and whether the part is actually sold.
Charge time. It is hard to game, easy to check, and makers mostly quote it honestly because a bad number there is embarrassing rather than commercially fatal. If a device fudges its charge time, assume everything else on the sheet is worse.