I have a theory about this: We group money in magnitudes of tens up to a million but then jump up from 10x to 1,000x:
1
10
100
1,000
10,000
100,000
1,000,000
1,000,000,000
That’s a huge increase but our minds like patterns so we instinctively feel that a billion must be about 10x a million and not the 1,000x it really is, thus leading to huge inaccuracies.