When we start the car, have you ever noticed all we need to do is to release the handbrake, hold the brake pedal, and then press the start engine button?
That is a simple and quick process we barely noticed. But do you know the history of the “Engine Start/Stop” Button? How those automotive engineers come up with the idea? What’s the story behind it?
Due to the fuel shortage and oil crisis of the 1970s, automotive manufacturers were trying to figure out how to reduce gas consumption. In 1974, the first vehicle to use the “automatic on/off switch” was the six-cylinder Toyota Crown, claiming a 10% gas saving in traffic. Later on, some big automotive brands (such as Fiat, Volkswagen, Golf, Audi, etc) implemented this technology in their models. Till today, manufacturers still need to figure out how to maximize the efficiency of the start/stop system to meet strict fuel economy standards by 2025. 
The development of the “push to start ignition systems” is revolutionary and just happened in recent decades. It takes time and effort to enhance the safety and user experiences for all drivers. Automotive manufacturers and designers learn the importance of great user experiences, which include failed and dangerous designs.
In 2015, the American auto brand Lincoln recalled 13,574 cars because of this button.  As shown in the below picture, the designers originally placed the button right below the “Sport Mode” button. If drivers want to switch to sport mode but accidentally pushed the “Start/Stop” button while driving at full speed, you could imagine how deadly dangerous it would be.
This should be called a dangerous “bad UX” in the automotive industry. Lincoln had to recall the cars and move the “Engine Start/Stop” button to the top. By fixing the position of the button, they lowered the risks of the drivers’ accidentally pressing “Stop engine” while driving at high speed.
Nowadays, most automatic vehicles have a big round button with standout colors near the steering wheel. Drivers will not miss it or get confused with other buttons on the dashboard. So, even the “Engine Start/Stop button” seems simple and old school, the technology and design behind it are anything but.