In a word, involvement. In order to truly take care of bees, a beekeeper needs to have hands-on contact with the hives, cleaning and adding frames and adjusting arrangements for temperature and collecting honey and insuring the health of the inhabitants and other procedures that are not always appreciated by the bees. Upset bees indicate that they are not happy with the beekeeper interfering with their hive by stinging!
The message behind the quote applies to more than just beekeeping. In most endeavors, the person who truly succeeds in any realm of effort is the person who risks getting injured or making mistakes or failing at first. The important thing is to learn from getting stung or being laughed at or loosing out. Taking the lessons from those kinds of experiences and applying the knowledge to future efforts enables one to eventually become a true beekeeper - or whatever other aim one has.