Sounds extreme isn’t it. Academically, if you want to achieve long term organization integrity then just throw out the wrong people. They are decease, resistance to change, and quietly spread negative behavior.
Other option, educate them and wisely transform them into your most expected result at high cost. Why high cost, it is not about training that will be given to them. It’s about time you will waste on it, while the competition outside is running.
Finally, it’s just a matter of choice. The way you want to walk in through. Which one is suit your culture and how strong you are.