Private (Pte) Ganesh Pillay Magindren's supervising officer was "completely out of her depth" in dealing with his mental condition, the coroner said on Tuesday.
That was because Captain (Capt) Jessie Goh, then a lieutenant, did not try to find out how to manage the full-time national serviceman (NSF), who had schizophrenia.
Pte Ganesh, 23, was found dead at the foot of his Sengkang condominium last July.
In an inquiry into the NSF's death, State Coroner Imran Abdul Hamid said he died from multiple injuries sustained from a deliberate fall from height, and that he had known it would lead to his death.
The day before his death, Capt Goh had given him 14 days of extra duties for not signing a logbook, reporting late for work and unsatisfactory work performance.
Mr Imran said: "(The punishment) is a daunting prospect even for soldiers without any mental issues.
"I agree with a previous witness who said Ganesh probably found it difficult to stomach the fact that he was given 14 days of extra duties after being at the receiving end of so many."
A stone-faced Capt Goh sat in the public gallery as the findings were read out in the State Courts.
She was the manpower officer at 24th Battalion Singapore Artillery and was directly in charge of Pte Ganesh when he was posted to the unit in November two years ago.
Pte Ganesh was assigned to clerical work as an administrative support assistant.
When he was posted there, Capt Goh interviewed him and found out that he was depressed and had been seeing a private doctor. When she asked what kind of doctor he was seeing, he did not tell her and she did not probe further.
In fact, Pte Ganesh was seeing a psychiatrist regularly for schizophrenia.
She knew only that he had been given the Physical Employment Status (PES) E9L9, the second-lowest medical classification given to servicemen.
Her computer system did not state why he had been given that PES status and she did not try to find out.