When the mantra among developers is "the only way to get a raise is to change jobs", and people are moving on a bi-yearly basis - yeah, you need to plan for cogs.
No amount of ownership is going to cover for an otherwise brilliant developer who jumps ship once the project has shipped its MVP. And if that brilliant developer wrote that project in, say, Haskell (because they wanted to learn it), that project is probably doomed from a financial point of view - a quality Haskell developer willing to do maintenance on an existing project will likely cost more than the project is worth in the first place.
The root of this problem does lie in management, but it's a self fulfilling prophecy at this point: employees have taken the lesson to heart. Even companies which do give fantastic benefits are going to still see high turnover, and need to account for that.
No amount of ownership is going to cover for an otherwise brilliant developer who jumps ship once the project has shipped its MVP. And if that brilliant developer wrote that project in, say, Haskell (because they wanted to learn it), that project is probably doomed from a financial point of view - a quality Haskell developer willing to do maintenance on an existing project will likely cost more than the project is worth in the first place.
The root of this problem does lie in management, but it's a self fulfilling prophecy at this point: employees have taken the lesson to heart. Even companies which do give fantastic benefits are going to still see high turnover, and need to account for that.