The battery on my Landcruiser sounded decidedly unhappy after three weeks of inertia over xmas. In fact it wouldn't even turn the engine. So I lifted the lid, plugged in this portable battery and turned the key. Well... it wasn't much better.
So I phoned the AA. Last resort. It should have been my first. Five minutes later a man in a yellow jacket and yellow van arrived, wired it all up and started my engine. And courteously expressed surprise that the battery (a very old one) had lasted this long. That's service.