Which is particularly relevant at consultancies where the product is a service.
If you join a consultancy group, and 2 months later quit with the client roster... is it really OK to poach all their clients to start your own consultancy?
All of these contracts are time limited, FWIW. E.g. non-solicitation doesn't mean you can never work your your colleagues again. It protects against someone leaving and then immediately poaching all employees within 12 months. After 12 months you're welcome to poach as much as you'd like.
Edit: Furthermore, non-solicits don't ban your colleagues from quitting with you, as long as you're not directly asking them to quit. If they make the decision independently without being lobbied by a former employee, it's not in violation of non-solicit.
For me that doesn't change anything. You should be allowed to tell your customer to come with you to a new business, the next day.
Companies know perfectly well that most of that value of the relationship is gone if you have to wait a year, so they pretend that time limiting is somehow reasonable.
The free market actually needs to be free.