Hoarce Dediu; Why focusing on a few products is hard:
But “focus” is the willful rejection of this theory. By saying no to alternatives you increase risk disproportionally to the reward. If you have the means to maintain a portfolio it certainly seems imprudent not to do so.
So why would someone want to focus?
The answer is that too much diversification is dangerous. It’s dilutive to everything the company uses to create value: its resources, its processes and its priorities. It dulls the mind and tarnishes the brand.