> "if you're actually using the PowerBook, a charge won't last nearly that long. Apple claims that the battery life is 3 hours and 45 minutes for a combination of wireless Web browsing and editing a text document, but only 2 hours and 15 minutes for DVD playback."
Also DVD decoding was an edge case — spinning up an extra drive and expensive decoding until the hardware, drivers, and OS all supported direct hardware decoding — which was relevant to people on planes but almost nowhere else in normal life.
Source: https://www.zdnet.com/article/powerbook-battery-shenanigans/