[jarlemag]

Originally Posted by Oberkommando der Kriegsmarine

As a matter of principle, every underwater attack should be so prepared and carried out that the launching of torpedoes can take place at the earliest possible moment. Favorable opportunities of attack may be lost by hesitating. If conditions allow, the submarine should therefore go to meet the enemy. It is wrong to keep ahead of the enemy and wait until he comes into range.

(https://maritime.org/doc/uboat/index.htm).