Some people prefer to work quickly and efficiently though they make mistakes sometimes, others like to work slowly but with certainty. But it is uncertain which one is better since working quickly would lead to a high efficiency while a lower pace in working would be more likely to make a difference. Perhaps it is only to say that different jobs may require different velocity in working.
For some people like professional athletes, a faster speed in working is better. Athletes, especially who play competitive sports, are often be required to move faster in the games. For them, a higher speed may mean a lager chance to win. Take basketball as an example. When you are playing basketball, you should move faster in order to avoid being impeded by the competitors. Even some mistakes are perceptive while you are in a high speed. The Spurs won the 2014 NBA championship because they pass the ball more faster than the Heat. Although they made lots more mistakes than Heats, they finally won the game. Thus, some people should work quickly and risk making some mistakes.
For other people like inventors, working with high speed and risks is also reasonable. Playing as the source of impetus for the development, invention in various ways are urgently needed. Consequently, inventors are responsible to make inventions as soon as possible in order to meet the need of the development. And, since the invention is the thing that never exist before, making them with certainty is impossible. As a result, the inventors should, and with no other choice, to work quickly and risk making mistakes. And I think any possible mistakes in the inventory would be permitted and forgiven by the public if its goal is reasonable.
For people with special works such as doctors, however, their work should finished with certainty even if its time consuming. Obviously, doctors' behaviors relate directly to the health of the patients. Any mistake in their work would be deadly to the patient. For example, if the doctor wrongly cut the vessel of the patient during an operation, the patient may loose his life because of the absence of fresh blood. So, people like doctors are supposed to work carefully even it cost a spate of time.
From the prospects above, it is truly vague for which one is better, quicker or more careful. But it is safe to say different jobs recommend different speed in working.