The investors don't manufacture those higher quality goods and services - their workers do. The investors collect economic rent from the worker's outputs.
And if the investors collect economic rent from the workers' output, then the workers collect economic rent every time an investor hires them for a project in which the investor loses money.
But under the standard Economics definition of "economic rent", a positive investment return from a project in which a person risked investment capital and the worker provided labor in exchange for a guaranteed wage is not economic rent that was extracted by the investor.