“11 months is one month shorter than 12.
10 months is 2x shorter.”
Your example is not formulated the same way as the statement in the article we were discussing.
“What is the life expectancy of batteries, compared to engines in gasoline-powered cars? Two or three times shorter?”
In your example, you’re multiplying a known difference between two time periods. How much shorter is the life expectancy of an ICE than the life expectancy that isn’t “shorter”? You can’t answer that, because we aren’t told what the base life expectancy is (the “12” in your example).
We’re left having to imagine what the author had in mind. If the author was thinking, e.g. 200,000 miles is the not-short life expectancy, and the actual life expectancy of an ICE is 150,000 miles — then “two to three times shorter” equates to 50,000 to 100,000 miles for the battery life expectancy.
However, if the author was thinking that 250,000 miles is a not-short life expectancy; then battery life is somewhere between minus 50,000 miles, and zero. An obviously absurd answer. The “X times less” formulation is always absurd, unless there’s the equivalent of the “12” from your example.
it is no different. What I gave as example is exactly the same. You cannot have a length or a distance or a time period that is two times shorter than another without it being negative. One could say that something is one third or one half the amount of something else, if that is what one means.It is not just the ability to use English but also the ability to imagine quantities and use simple arithmetic. If one cannot do that then one probably should not be expressing opinions or trying to lay out facts for the edification of others