And that lesson is transparency.
The ex-Boost Mobile boss became a key figure in the mysterious saga that saw Kostecki sit out the first two rounds of the season.
Boost was still a personal sponsor of Kostecki when the driver temporarily parted ways with Erebus Motorsport over what was thought to be a rift with senior management at the team.
Adderton was publicly critical of Erebus Motorsport and in particular CEO Barry Ryan, while also taking aim at Supercars for its handling of the matter via his popular social media presence.
That criticism continued even after Kostecki returned to Erebus, which spelt the end of the personal sponsorship deal between Boost and the reigning Supercars champion.
Throughout the saga details have been thin on the ground, something that has proven frustrating for the Supercars fanbase.
And that’s why Adderton feels transparency is the key lesson for all sides to learn.
“I think transparency is critical in today’s world,” said Adderton on the KTM Summer Grill.
“And I think the lack of transparency that took place during the whole Erebus/Brodie Kostecki incident was probably the biggest learning lesson for everybody – and I think that includes Erebus, and that includes Supercars, and I think that includes Brodie. You have got to be transparent.
“Fans expect you to tell them what’s going on, and if it’s bad, it’s bad. If you’re upset, you’re upset. We can deal with that. What we can’t deal with is constant story changes and lies.
“I was disappointed because we’d supported Brodie, he’d asked us to support him, and I went out on a limb to support him. And then at the 11th hour was thrown under the bus when they all decided to have a kumbaya and high five each other and get back in the car.
“To me that was disappointing. So hopefully transparency is the thing that most people understand.”
Ryan has consistently said that Kostecki’s absence from the Bathurst 500 and Albert Park events was a private matter for the driver, something he reiterated during his own appearance on the KTM Summer Grill.
Watch the full Peter Adderton episode below.