Planning for each day: a habit of every good manager

Do you arrive at work in the morning without knowing quite what you will be doing that day or what exactly you want from your team, so you come up with tasks "on the run" or as the tasks come to you? Some say this attitude is completely wrong and will never push you closer to your goals (not to mention the fact you are not providing a good example to your team). The key to achieving goals is daily planning.