The usual meaning of this old saying is that when we start a new task or are in a new environment, we make a much bigger effort and probably produce better results.
Anyone who has started in a fresh job will know the truth of this saying. So often, new tasks seem fascinating, we give them a lot of energy and seem to get on with them very well. Then, somehow, when the new job etc becomes a routine (even a routine we enjoy) the "new broom" feeling seems to fade, and with it that sense of eagerness to start the day's work.
This is one reason why some people like to change workplaces and even careers regularly; some feel that as soon as a job becomes known and/or manageable, it also becomes boring.
Perhaps the other side of this saying is the phrase "Familiarity breeds contempt." Metaphorically speaking, it's much less fun sweeping a floor you know well!
Anyone who has started in a fresh job will know the truth of this saying. So often, new tasks seem fascinating, we give them a lot of energy and seem to get on with them very well. Then, somehow, when the new job etc becomes a routine (even a routine we enjoy) the "new broom" feeling seems to fade, and with it that sense of eagerness to start the day's work.
This is one reason why some people like to change workplaces and even careers regularly; some feel that as soon as a job becomes known and/or manageable, it also becomes boring.
Perhaps the other side of this saying is the phrase "Familiarity breeds contempt." Metaphorically speaking, it's much less fun sweeping a floor you know well!