Aviation businesses ie schools and small charter companies can be viable if the owner is also the chief pilot, is closely involved in everyday operations and is a good financial manager, with a handful of loyal, trusted, efficient personnel. Owners, not committees. Once you start getting so big you need an army of managers and a revolving door of staff then the brochures will get shinier, the ponzi scheme will grow but quality will suffer until the bubble bursts and the student files end up in a skip along with their careers and massive loans. The key to success is to find the sweet spot of hours flown, cashflow, staff and the right number and type of aircraft for your unique market, be adaptable, rather than try to be the biggest and trample or undercut your colleagues. Most schools don't last long enough to find the sweet spot as they are only chasing cash flow, even when it is flowing out faster than in. I've seen so many come and go and it is like groundhog day. I've had flying school owners whining that they can't afford to pay their bills, whilst driving around in a $90,000 car.
So yes, having a cohort of long term, well paid, happy instructors who get on well is a very important part of success and of course work satisfaction. Students love continuity, they don't want a new instructor every few weeks, who is champing at the bit to get out of the low paid toxic environment they have found themselves in for bigger skies. A good instructor will see it as a long term career with many benefits. Like everything, you won't get anything out of a job if you don't put anything in. Life is what you make it.