Why do F1 teams use special liveries at testing?

Formula 1 teams frequently debut special liveries during pre-season testing, a practice explained by F1.com. These unique designs often serve dual purposes: either to camouflage crucial aerodynamic details, as famously seen with Red Bull in 2015, or because teams haven't yet unveiled their official season liveries. For instance, teams like Cadillac and McLaren are sporting temporary designs at the Barcelona Shakedown, ahead of their full reveals in early February. While some, including Red Bull, Racing Bulls, and Ferrari, have already launched their 2026 liveries, others prefer to keep their final looks under wraps until their official team events. This tradition of special liveries adds an extra layer of intrigue to the pre-season build-up.