If you're paying an engineer $100k to add 150k worth of value to your product, the true value of their work is $300k: $150k worth of value to you, and $150k worth of value that isn't added to your next closest competitor.
That model seems to assume:
- every employee who leaves will go to close competitors
- their work for that close competitor will be perfectly zero-sum to their work for your company
- the next best replacement employee your competitor would otherwise hire would be worth 0 to them