[carpedimebagjoe]

KSP should include a black-box warning:

Installing this will affect your sleep schedule, your sex life, your relationships, and you will be late for work.

[Syonyk]

... but you will understand orbital mechanics deeply. Play accordingly.

[erwinh]

Unless you play it at work!

Had a summer job at a web-dev shop some years ago already where the boss had a burn-out, but then to get back to a nice work/life balance he played ksp the entire afternoon at work and let all the devs play too :p