A woman who died from sepsis accused hospital staff of leaving her "to rot like a piece of meat" days before her death, her daughter has said.
Linda Prydderch, 60, died at Wrexham Maelor Hospital in 2015, four months after going in for a ruptured hernia.
Her case was one of 16 highlighted by the Public Services Ombudsman for Wales as poorly handled patient discharges.
Betsi Cadwaladr University Health board apologised for the way the discharge was handled.
Mother-of-three Mrs Prydderch went into hospital in November 2014 and ended up having three operations, but by February her condition deteriorated.
She was transferred to a community hospital but staff had not received the appropriate training needed for her care, Mr Bennett's report said.
Mrs Prydderch was transferred back to Wrexham Maelor with an infection for the day and then readmitted in March after her condition deteriorated.
She was diagnosed with sepsis and died on 13 March 2015.
Mrs Prydderch' daughter Leanne Pugh said: "The way they treated my mum was disgusting.
"I think they were trying to get her out of the hospital because she was shouting in pain but she couldn't explain where the pain were.
"My mum's word were 'they've just left me here to rot like a piece of meat'."
Other cases around Wales highlighted by Mr Bennett included a man who was discharged after being knocked unconscious on a night out but later collapsed as he had bleeding on the brain.
"The cases in my report, while not typical of everyday service in our hospitals, are alarming, and have resulted in unnecessary suffering," Mr Bennett said.
"I would encourage all health boards to read this report and ensure lessons are learnt so other patients do not have to endure the same experience."
The Welsh Government said patient safety was "an absolute priority".
A spokesman added: "Following a review by Health Inspectorate Wales earlier this year, all NHS organisations are putting improvement plans in place.
"We are also considering what further action may be needed and this report will help inform this work."