Veteran climbers from New Zealand and Nepal are warning of a 'recipe for disaster' unfolding on Mount Everest with the climbing season underway.
They warn increasing numbers of inexperienced climbers are attempting the summit with untrained sherpas in cut-rate expeditions that count on half of groups - of up to 60 or 70 climbers - giving up early.
Many climbers are now six weeks into their haul up to Everest base camp, and abound a fortnight from beginning to try to get to the peak of the world's highest mountain. Some have paid $NZ100,000 to be there, others less than half that.
Guy Cotter, who runs Wanaka's Adventure Consultants, charges the higher price and said a climber would get what they paid for from emerging cut-price Nepalese-run operators.
"One of the worst things about it is that a lot of these operators are not asking for their clients to actually have any previous experience before they turn up on the mountain," he said.
"So there's a lot of people on Everest who have done sometimes absolutely no climbing at all."
Mr Cotter said it was a recipe for disaster.
"Some of these people - with no experience - if they get high they just don't know how to look after themselves and a lot of them suffer terrible frostbite and even worse.
"Over the years some of these operators have lost many, many people and most of these incidents were avoidable."
The cut-rate expeditions began around 2010.
Mingma Sherpa runs Seven Summits and charges $NZ42,000 for Everest. He rejects the idea climbers were dying by using local companies.
"My company, every year we have a thousand climbers in the mountains. Everybody knows mountains are dangerous, but you check - my company has organised many expeditions. Many other companies also have many accidents, you know."
Excluding a large 2014 avalanche and last year's quake, only seven people have died on Nepali-run expeditions since 2006 - four of them foreigners.
UK-based New Zealand veteran, Russell Brice, who runs Himex, told AFP some new operators were endangering lives.
American Damian Benegas has guided climbers on Everest for 17 years but was now unable to compete on price. He said Nepal needed to be honest about the human cost of cut-rate climbs.
But Mingma Sherpa said Western companies were worried about their market share.
"I will give them same sherpa and same food, same oxygen ... Whatever they are charged for 80,000 [US dollars] or 55,000 yeah. I am not businessman, I am not making money from mountain ... my mountain friend who like to go mountain, I will make dreams for them to go Everest."
As for his guides and sherpas, Mingma Sherpa said it was true there were very few qualified Nepalese guides, but his young sherpas worked their way up.
Nepal Mountain Guide Association president Dorjee Lama told RNZ News a climber was more likely to die with the low-cost companies because they did not provide quality support such as the right logistics, trained guides or oxygen to cope with the number of climbers.
Billi Bierling has climbed five 8000 metre peaks, and helps run an Everest database in Kathmandu.
She said cheap operators were cutting corners, and only very experienced climbers should use them for their cheaper base camp facilities, before striking out for the summit on their own.
"Of course it's a recipe for disaster. If you have a sherpa who's never climbed Everest before, and maybe he has a little bit of experience walking with crampons, and you have a client who's only climbed Kalapathar [in the Everest foothills] before then, bloody hell, yes, it is a recipe... I think the climbers they really have to make a decision to choose rightly."
Mr Cotter said people who did not have a positive experience with their guide company were not sharing their stories.
"They go home with their tails between their legs and say nothing.
"And that's another reason why this story hasn't really come out much cos nobody's going to turn around and say, 'I made a really big mistake'."