And how, exactly, do you figure that? Typical IOD (ignition off draw) for these types of modern vehicles is around 50mA (milliamps). Even without periodic bursts of higher current draw, that's 1.2AH's (amp hours) per day, or 8.4AH per week. Our batteries are rated somewhere around 50AH total capacity. That's TOTAL capacity - meaning at the end of those 50AHs, the battery has nothing left - not even enough to energize the starter solenoid, let alone turn the starter.
It's very possible, with several short trips prior, that leaves the battery in a less-than-fully-charged state, that an extra week of sitting, drawing down another 8.4 AHs, will draw enough out of the battery that it can't deliver enough current to crank over a cold engine. Or, even if it could, it wouldn't be at a high enough voltage to keep the computer and other electronics happy (in the old days, it didn't really matter if your battery voltage dropped to 10V while cranking... the coil still fired. Today's fuel injection systems don't like it when the voltage drops much below 11.5V). At 10 weeks, it would be COMPLETELY drained, probably to the point beyond recovery.
This is why I keep my vehicles on battery tenders, and why I got 16 YEARS out of my last set of Optima red tops in my '03 Cummins.