A cancelled procedure and the early discharge of a patient were among more than 450 complaints to an NHS trust during a six month period.
A total of 453 grievances were lodged with the Mid Yorkshire Hospitals NHS Trust between April and September 2019.
One case study, which was revealed in a report, told how a lack of communication between staff led to a patient's procedure being cancelled, as their pacemaker needed to be monitored.
Another complaint came from a patient who said they "did not feel fit or well enough to be discharged" after surgery.
However, the overall number of complaints to Mid Yorkshire, which runs Pinderfields, Pontefract and Dewsbury Hospitals, is down 13 per cent on this time last year.
And the trust has been told by the health ombudsman that they are "over-reporting complaints", though they were praised for being transparent by doing so.
According to the latest figures, the organisation was the 16th most complained about NHS trust in the country.
Speaking at a trust board meeting on Thursday, director of nursing, David Melia said: "We have improved our ranking (among NHS trusts across the country), if that's the right word, so that we are no longer in the top 10 most complained about trusts in the country.
"Learning lessons is important and how we show that, so there are some examples in the report of some of the issues that have come up and the things we've changed."
The report showed that around 40 per cent of people felt either "very" or "quite" confident that the trust would learn from a complaint.
Mr Melia added that convincing people improvements have been made was "something we need to do more of".
The board was told that a significant number of complaints related to the speed of treatment a patient received.
But the trust's chief operating officer, Trudie Davies, suggested clinical staff were being trapped in a "vicious circle", where they were unable to treat patients because they were dealing with complaints that they'd been too slow to see someone previously.
She said: "I think our staff would find it very reassuring that they're not being blamed for something they can't help.
"We've tried everything and we can't see patients any more quickly than we can at the moment. We just can't."
Bosses are considering sending out more "standardised" responses to this kind of complaint in future, in a bid to free front line staff.
Mr Melia added: "I think it's about keeping the balance between assuring somebody's concerns, being respectful, but not overburdening someone (a staff member)."
Local Democracy Reporting Service