Tesla CEO Elon Musk says the company has scrapped plans to offer an air-ride suspension on its Model 3 sedan. The announcement goes back on a promise made by the executive in 2017.

On Sunday Musk took to Twitter to respond to a question about the availability of an air suspension for the company’s entry-level Model 3 sedan. Musk didn’t mince words, flatly stating that Tesla has “no plans to introduce air suspension on Model 3 at this time.”

That Tweet is in stark contrast to another Twitter statement made by Musk in August 2017. When asked about the availability of an air suspension for the Model 3 back then, Musk stated that Tesla was developing such a system for the dual-motor variant of the Model 3 sedan. Musk even went as far as to say air ride-equipped Model 3s would be available in early 2018.

However, that Tweet never came to fruition, and it looks like an air-ride Model 3 never will, either.

Musk didn’t give a reason for the cancellation of the Model 3’s planned air suspension, but a couple of factors are likely in play. The first is simplicity. Tesla had a difficult time ramping up production of the Model 3, and an air suspension, with all of its extra componentry and complexity, would only add to the company’s production bottleneck.

Another factor could be Tesla’s desire to better differentiate between its model lines. By keeping air suspensions exclusive to the company's flagship Model S sedan and Model X crossover—both of which come standard with air ride—Tesla can better maintain those vehicles’ premium positioning while also providing enticement for customers to upgrade from a cheaper Model 3 to a more-expensive Model S or X. 

It remains unknown if Tesla is planning an air suspension for its upcoming Model Y crossover, which will be based on some of the Model 3’s hardware. However, an adjustable suspension would make more sense in that application as it could give the SUV a bit more ground clearance for a dedicated off-road mode.