Growing is a natural process, like planting the seed of a herb in a small pot for your cooking. Basil. Parsley. Rosemary. Ginger. Aromatic, sweet or pungent.
A tiny seed in a small pot with some dirt. With the right environment and nutrients, the plant starts to appear. A little stem. A little leaf. Day by day, the plant flourishes, giving an abundance of leaves, flowers or fruit.
Soon enough, the small pot is not big enough. If the plant doesn't change pot, it may suffocate, contract disease, wilt and die.
People are like plants. When people learn, they grow. There comes a time when people need to change pots. In a limiting small-pot environment, people stagnant, become cynical or leave.
There is nothing wrong with outgrowing. It is a natural process, like life. Outgrowing may seem like giving up, quitting or being disloyal. It might be. Couldn't it also be of wanting more or something different?
Don't be upset when people choose to leave. Don't beat yourself up for pursuing something else.
It's your life. Only you can live it.