According to the game's artist, Masato Kato, the game's difficulty was the result of an accident, however the development team decided to not try to fix the difficulty as they enjoyed it.
Contributed by gamemaster1991
Hideo Yoshizawa originally wanted to make the player appear in the middle of the stage when losing a life, but one of the programmers lied about putting the feature in and had the player appear at the start of the stage instead.
Contributed by Artwark