Take Formula One cars as an example. As part of the programme, pre-season testing on F1 cars is carried out for all teams in the sport, but the teams don’t focus too much on setting the fastest lap; this is for race days. Instead the teams carefully analyse system functionality, to make sure all the systems speak to one another and work correctly.
Data is collected and upgrades are made. The purpose is to find the weaknesses and issues and rectify them before the first F1 Race of the season, to enhance the car’s performance as much as possible.
Take pre-season testing away, and teams could be faced with all sorts of issues, some which they might have not been aware of, which could ultimately place their drivers at risk and cause major performance issues, not just once, but at each race.