Yup, if you don't then your landlord gets all the value. You get a 10 year lease, build a successful restaurant (if you make it past the dreaded first year) and then when your lease expires your successful restaurant has helped increase the land value in the area and the margin you worked up to evaporates when you sign a new 10-year lease that is more expensive because the value of the land has gone up (partly due to your success).