Finally learning some lessons!

The century date problem as it was known before Y2K was first described in the 1950s but people assumed it would be a moot point long before it was a problem.

When some of those mainframes were still in use in the 70s it was brought up again but nothing was done because it was assumed that it would be a moot point long before it was a problem.

When some of those mainframes or software were still in use (banks, oil companies, the IRS, etc) in the 90s it was finally seen a as a problem and cost billions of dollars to fix.

Then it happened again in 2020 because it turns out that the fix was to kick the can down the road again.