Mercedes boss Toto Wolff says that promoting Pascal Wehrlein to a race seat with the Silver Arrows team would have put the young driver at risk of destroying his career.
Mercedes opted to replace world champion Nico Rosberg with Williams' Valtteri Bottas, thus turning away the opportunity of rewarding its junior driver with the drive, a move many have criticized as it called into question the very principal of nurturing young talent.
But Wolff defended the decision on the grounds of defending Wehrlein's best interests.
"He is fast and brilliant and he was always considered," Wolff said.
"But he is in his development phase. He must be able to make mistakes and learn. And he could not have done that with us.
"Look at Sergio Perez, Heikki Kovalainen or Kevin Magnussen. They arrived too early at McLaren and were not well enough prepared."
Compared with Red Bull's bold move of hiring Max Verstappen at just 17-years-old and honing his skills before promoting the young prodigy to its 'A' team, Mercedes approach appears timid. But Wolff dismisses the comparison.
"We must not forget that even Max had his development phase. Red Bull prepared him perfectly, first with drives on Friday morning, then doing a season and a half at Toro Rosso.
"And even when he arrived at Red Bull, he did not have to fight for the world title or compete with a driver like Lewis Hamilton. He one won race versus nineteen for us, and was not always at the front.
"And he made mistakes, as in Monaco or Austin, which a young driver must be allowed to do. Because there are no second chances."
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