Call centres, aggressive selling and general incompetence are causing "service rage" among British consumers, a report has said.
Call centres are among the top annoyances for consumers
Businesses have been described as "dishonest" and "ineffectual" in a survey from the National Consumer Council (NCC).
Its report concludes that businesses could lose money if they do not nurture better customer relationships.
Business leaders said firms were doing their "utmost" to please customers.
The report said firms in the financial services, telecoms and utility sectors were named among the poorest performing.
"Robotic" call centres, hard-sell marketing, missed appointments and bad after-sales services were among the most frequent complaints made by customers.
Some companies were criticised by survey respondents for being "sneaky and dishonest" while others were labelled "incompetent and ineffectual".
The NCC said 800,000 people complain to Trading Standards departments every year while around 75% of shoppers have problems with purchased goods.
It suggests one specific member of staff could be assigned to customers from start to finish to improve service standards.
Philip Cullum, NCC deputy chief executive, said: "We're seeing more and more service rage, with infuriated customers punishing companies for hopeless performance.
"The scale of company ineptitude must amount to many billions of pounds of lost profits."
The NCC report is based on research carried out over 18 months, including a survey of 2,000 adults in Britain carried out in October 2004.
A spokesman for the Forum of Private Business, which represents small to medium size companies, said: "I can assure you there are a lot of business owners out there busting a gut to ensure that their businesses remain profitable in an extremely difficult tax and regulation environment.
"Certainly these businesses are doing their utmost to assure customers they get what they want."