Only certain classes of officers if I remember correctly, and it more likely was motivated by preventing the leaking of intelligence under interrogation by the

Only certain classes of officers if I remember correctly, and it more likely was motivated by preventing the leaking of intelligence under interrogation by the enemy, rather than really being about preserving honor. Of course it's probably easier to carry out seppuku if you convince yourself its honorable, rather than to just do it based on rationality. Not all failure results in capture, so one particular failure scenario does not speak of the general view on failure.