In the fifties. Lotsa cars sold, a new model every year.
This example isn't the greatest color, but still easy on the eyes. At the time the '58 was the most expensive Chevy ever manufactured because they were lining up all the year to year changeovers across all the GM lines and this one needed a one year only complete redo to fit into the family.
"The real reason for the single-year Chevy is simply a scheduling detail. Back in the mid-1950s, GM planners decided sharing body platforms clear across the GM line—and that meant Chevy, Pontiac, Oldsmobile, Buick and Cadillac—would reduce costs and make sense going forward. From that point on, a two-year cycle with a minor facelift after the first year would be the future path for all divisions. The 1959 model year would be the platform to do this because Cadillac, Buick, and some Oldsmobiles were coming off of their second year of bodies, having received all new architecture in 1957.
What this meant was that Chevy got pulled forward into this schedule, leaving the 1958 Chevy as a one-year-only anomaly."
https://www.motortrend.com/news/the-most-expensive-chevy-ever-made/