Our bonding isn't such a sure thing! The chances are small, but circumstances may lead to my leaving the court and pursuing a different path in my life...or perhaps, for the Prince to no longer find me a suitable partner and have me dismissed. It would be unfortunate, but it is possible. The Prince's duties also mean he cannot spend all his time with his partners -- it woud not be proper -- so it's also impractical in that way.

So, we learn from the consorts who serve the current leader of the country instead, at least for the first few years. When things are more surely established, we may spend more time with the Prince and assume more authority of our own.