Years ago, there was only one way to become a baker or pastry chef, and that was to apprentice with a master craftsman. The apprentice learned by doing, repeating the necessary skills, year after year, until the skills were mastered. If bakers and pastry chefs understood their ingredients or why they did what they did, it was only after years of experience. Mostly they knew what to do because they did what they had been shown, and it worked.
Today bakers and pastry chefs have more challenges. They must master more skills. They must adapt to faster-changing trends. They must learn to use a wider array of ingredients from different cultures. They must learn to use still more ingredients devised in the chemist’s lab. They must learn all this in a shorter length of time.