Vantaggi
You can take responsibility early on and make a swift career progression until you hit a certain ceiling that has been established for decades. The company places high importance on your attitude, more so than your skills, as the general belief is that everything you need to learn in order to do a good job (or have a successful career) can be learned within the organization. Middle management is very approachable. International careers are open to anyone who is interested and willing to step out of their comfort zone. In some positions, you have the chance to become a franchise partner while remaining employed at the company, offering the easiest way to start your own business. The company is very forgiving. If you make a mistake, you will rarely face serious consequences.
Svantaggi
Tunnel vision and a lack of inspiration are problematic. The business model, which follows full vertical integration, turns the company into a cash cow, obscuring the very poor quality of some individuals in middle and upper management. Very junior employees at the very start of their career will find good mentors, but after 1-2 years, top potentials will realize that there's nothing more to gain from them. One reason is the tunnel vision that focuses solely on internal growth (great for internal career progression, of course) and completely excludes external hirings for management positions. The other reason is the lack of investment in external training and development. These two things combined create a very dangerous combination. That's why I foresee the company failing in the long run (even if at the moment this seems impossible due to the strong profitability and expansion).