(I think modern tyre shapes at 1920s rubber prices might have cost a significant fraction of the car? Back then, they were not only small and narrow compared with today, but they were also much thinner — which is probably why Bibendum, the Michelin Man, is made of tubes)
The Allies miscalculated with the Maginot Line, because they hadn't realised the Axis might invent and produce synfuels.
The Axis miscalculated with cutting the UK off from its rubber-producing colonies, because they hadn't realised the Allies might invent and produce synthetic rubber.
(I think modern tyre shapes at 1920s rubber prices might have cost a significant fraction of the car? Back then, they were not only small and narrow compared with today, but they were also much thinner — which is probably why Bibendum, the Michelin Man, is made of tubes)
The Allies miscalculated with the Maginot Line, because they hadn't realised the Axis might invent and produce synfuels.
The Axis miscalculated with cutting the UK off from its rubber-producing colonies, because they hadn't realised the Allies might invent and produce synthetic rubber.
https://en.wikipedia.org/wiki/Synthetic_fuel#History
https://en.wikipedia.org/wiki/Synthetic_rubber#World_War_II
EDIT: more on rubber; those colonies had earlier yanked the market away from Brazil: https://www.k-online.com/en/Media_News/News/April_2014_From_...