Because the focus is lost.
Focus is the key to suceed. Masters are good only in one thing because they foucs hard on it. Sometimes we meet people who like to do everything and that is why they are good at nothing. Businesses/freelancers like to be busy and that's why they pick up everything that comes across their path, without giving it a thought whether the opportunity is in sync with their core philosphy or not and they fail not because they didn't have opportunities but because they had too many of them.
So, what's the solution?
Build your work around selective things and say "no"to the rest. Ditto for the personal life. Pick 4 values and stict to them. At work, build your team around 4 key result areas and say no to rest. If you try to do everything all the time, you wouldn't stand anywhere.
So, the thought of the day is - Stay Focused. If you want to succeed, it is the only way to go.