Sounds exactly like regular espionage to me. Hiring employees from competitors with "5 years experience in this exact line of work" really is espionage on a small scale.

They will use their knowledge of what doesn't work, and how not to approach problems gleaned from their previous employer to solve your problems much quicker.

Previous employers cost to develop a space laser: 5 years.

Time to re-invent space laser when you already know how to do it: 6 months.