Lawson thrust himself into contention for a potential drive next season after being thrown in at the deep end at the Dutch Grand Prix after Daniel Ricciardo broke a bone in his left hand in a practice crash at Zandvoort.
The 21-year-old New Zealander then conjured an astonishing performance in Singapore where he scored the team's best result of the season in finishing ninth.
At that stage, it appeared Lawson was in the reckoning for a full-time berth, only to be told before the following weekend in Japan that he would have to continue to bide his time by remaining in his reserve role for both Red Bull and AlphaTauri.
AlphaTauri ultimately determined that Ricciardo's experience was more crucial to ensure the team moves forward next year from its current position at the bottom of the constructors' standings, in tandem with current driver Yuki Tsunoda.
Assessing why Lawson was overlooked, Bayer said: “We had lots of discussions about the future of the team and our shareholders said ‘We want you to continue and educate young drivers but we also want you to be successful'.
“Ultimately, you can't have both. You can't have two ‘young' drivers in the team. We looked at what we needed to deliver that, and we finally came to the conclusion that, first of all, we only have two seats.
“Daniel offers a lot of expertise, especially when it comes down to the setup of the car, which is something that we have struggled with.
“Yuki has grown over the years, is achieving, and is now coming to the pinnacle of his performance curve, so we thought those two make the right team.
“On top of that, it's also good to have somebody like Liam just behind them, to keep the fire warm under their seats and make sure we progress as a team.”
The feeling is AlphaTauri has altered its philosophy from being a team that has continually nurtured young talent.
There was an argument to suggest that after three years with the junior team, Tsunoda's time had run its course.
Bayer insists, though, AlphaTauri will always provide opportunities for upcoming drivers, but that now has to be tempered by the needs of the team in an increasingly competitive marketplace.
Suggested to Bayer that AlphaTauri's reason for existence was no longer as a platform for young drivers, he replied: “It is but not absolutely so.
“The reality today, if you're looking at the grid, it's so competitive, so tight, with every tenth of a second being fought for.
“We came to the conclusion that in order to be contenders for the top midfield, we need one experienced driver.
“But we'll continue to grow young talent that ultimately shall end up in Red Bull Racing.”