Tens of thousands of callers to the police non-emergency line have hung-up in frustration at long waiting times.
A total of 135,389 calls to Welsh police via 101 were abandoned or redirected last year - almost 14% of all calls.
Wendy Lewis, from Swansea, waited for 22 minutes while trying to get help for a young mother who was being harassed.
"In the end I gave up," she said. Police bosses said improvements had been made.
Introduced almost a decade ago, the 101 service is for reporting non-emergency incidents such as criminal damage or stolen vehicles.
But figures obtained by BBC Wales show that since 2013 the number of calls abandoned has risen across Wales' four police forces.
The highest rate of abandoned 101 calls was in the Gwent force area, where just over a fifth of calls - or more than 47,000 - were dropped before being answered in 2017.
There are no standard times for answering calls, with each force setting its own targets.
Swansea councillor Ms Lewis said she had hung up more than once when she was trying to report an incident.
She said: "There was a young mum with little babies who was very concerned about two individuals knocking on doors asking for money, cigarettes, and she was very frightened.
"I was on the phone for 22 minutes....in the end I gave up.
"So these individuals had gone then and we don't know what they were up to… and I was angry, very angry, because there's nothing I could do."
Recently she called the non-emergency number after an off-road bike was seen driving repeatedly past a school doing "stupid things".
She said she was so concerned that a child would get hurt leaving school, that after being on hold to 101 for 20 minutes, she put the phone down and called 999, but said she felt "guilty" for calling the emergency number and apologised to the call handler.
The overall rate of abandoned calls last year actually reduced from 2016 - when more than 150,500 were dropped. But the number has risen across all four forces since 2013.
Police stressed some calls logged as abandoned would have been redirected - to the 999 emergency line or force websites - but acknowledged many callers were ringing off in frustration.
Demand for the 101 system has increased since its launch, with growing numbers of callers ringing about non-police matters such as mental health concerns.
It costs 15p per call, regardless of waiting times.
Fiona McAllister from Cardiff said she had tried to call 101 numerous times to report drug dealing in her neighbourhood but had been annoyed by the long waiting times.
"One of the problems we have where I live is drug dealing," she said. "There a lot of drug dealing... I get the feeling a lot of people are very frustrated out the 101 service.
"The current service in the current form just isn't working properly.
"Invariably, you're on the phone for a long time waiting to get through and therefore you have to be persistence and determined to wait because typically it can take about 20 minutes."
She added that calls to the service from mobile phones should be free and feels that sometimes details passed on to the police can end up in a "black hole".
Alun Michael, Police and Crime Commissioner (PCC) for South Wales - where more than 36,600 calls to the 101 line were abandoned in 2017 or redirected - described the figures as "worrying" and said they risked damaging public confidence.
Mr Michael said: "It certainly doesn't help the relationship between the police and the public…some of the issues may not be an emergency but will be serious and important issues, so we want the public to be able to get through."
While the South Wales force ranks ahead of most for speed and quality of response, Mr Michael said this had "lulled us into a bit of a false sense of security" in the past.
Improvements to call-handling were introduced in March.
'Embracing new technology'
Dyfed-Powys PCC Dafydd Llewellyn said more resources had been allocated to call handling - particularly during the tourist season - after he raised concerns with chief officers about waiting times.
He added: "We need to embrace the new technologies, Facebook and Twitter…we're not recording crime directly on these social media platforms but there are opportunities for us to use these platforms to engage increasingly with the public.
"We're trialling using things like WhatsApp for rural communities, where we have a new strategy that we've launched."
Supt Vicki Townsend, of Gwent Police, said: "Work is currently ongoing to identify repeat abandoned callers, in an effort to more accurately understand the reasons for their abandonments."
Ch Insp Jeff Moses, of North Wales Police, said calls should be regarded in the same way as those to energy suppliers "where a swift response cannot be guaranteed and should not be expected", adding the service had been a "victim" of its own success.