Last week one unfortunate Abbey customer had his current account sabotaged after giving a call-centre worker a bad rating.

Sadly, such stories are becoming increasingly common and frustration with call centres has become a fact of life. Times Money hears daily from angry readers who have been let down or badly treated by call centres. Life on the other side seems equally frustrating, according to the myriad online forums, blogs and YouTube videos, where some of the UK's one million call-centre workers vent their spleens.

There are 5,180 call centres in the UK, employing 3.5 per cent of the working population. These workers are the front and often only line of communication between a company and its customers. While inefficiency, mistakes, delays and rudeness are commonplace, our investigation into the industry also indicates that customers are falling prey to dirty tricks and even fraud.

We asked a long-serving executive and a call-centre employee, who have worked for a number of different banks and insurers, to give their behind-the-scenes accounts. Both are still working in the industry and have asked to remain anonymous.

The industry executive

“Call-centre managers would rather employ too few than too many staff, because they do not want workers underemployed, which is why there is always a queue when you call.

“Productivity is measured by ‘abandonment rates' - the percentage of customers who tire of waiting and hang up. The industry average is about 5 per cent. A lower rate implies underemployment; a higher rate suggests that people are waiting too long. You would think that centres always try to improve response times, but those with low abandonment rates could be trying to increase the time that you spend waiting.

“The average salary of a call-centre worker, including bonuses, is about £15,000. The bonus can be as much as £3,000, so it makes a huge difference to their salaries. The usual term of employment is between one and two years before they leave, often to go to another call centre.

“Working life is tightly controlled, even with designated toilet breaks in some cases. Average call lengths, sales and acceptance rates for sales staff are all monitored. Bonuses for sales staff are determined by the ratio of sales to the number of calls, so if an employee is on a call and thinks that a customer is not going to buy, he or she will do everything to get the caller off the phone, including hanging up.

“Problem-solvers have hourly targets, such as 12 problems an hour. If each call lasts about five minutes, and after four a resolution seems unlikely, they may hang up. If they realise that they are unable to resolve a complaint and the customer is becoming irate, they may hang up or say 'try this and call back'. This allows them to tick the approval log.

“Giving customers false names is another common tactic. In Indian call centres they often use westernised names to make callers feel more comfortable. Another trick is for a call centre to use only a handful of names, such as Sue, Laura, Steve and John, because it makes people feel more comfortable if they think that they are coming back to the same person.

“Staff also breach security. There is a risk of fraud because employees often write down card numbers and pass them to friends outside the office. Of course, good call centres try to eliminate this, but it is impossible to do so completely.

“Not all centres record calls, and with those that do, it is not uncommon that records cannot be found.”

The call-centre employee

“It is the commission that drives wrong behaviour. Productivity is determined by the number of calls. Staff are judged on the number of calls rather than the quality. Sometimes staff cut off the call even before they speak to the customer, but this will still register as a call, so will still boost the figures. This is gross misconduct but normally they will merely receive a ticking off.

“There are a few audit checks in place to prevent this from happening, and the better call centres have ironed it out, but it is quite common.

“A lot of staff take their jobs less seriously because they assume that they will be gone in three months. There is very little staff loyalty and people do not see call-centre jobs as a lifelong career.

“In insurance sales centres, advisers get to know the type of details that will drive up the price of a quote, such as higher mileage or expensive makes of car. So they will often offer an artifically cheap quote to win the business. If a caller agrees to a policy priced on false mileage information, for instance, he or she could be underinsured when making a claim.

“If someone asks to speak to a manager, staff will not always put them through. They might, instead, put the caller through on to the team leader, or even another adviser. Staff are meant to make a note of complaints on the customer's file, but because they move immediately from one call to the next, they forget to log the notes. Often, they do not want to log the notes because they are worried about how it will reflect on them if the call goes higher up.

“Some staff use customers' credit card details to buy things on the internet. How much of this goes on depends on the line manager: some turn a blind eye, some don't see it.

“There are lots of industry associations, which are great, but they are not able to analyse all the data from every centre. More consistent training is required. Without it, we will encounter the same problems of workers being bored and angry and wanting to find shortcuts.”

Dirty tricks at a glance

Fake names: staff in many Indian call centres use a handful of Western names, such as Steve, so that customers think they are coming back to the same person

Fake quotes: operatives selling insurance know what bumps up premiums and may skip vital questions to flog invalid cover.

Hang-ups: call-centre workers take commission on resolved calls. If your problem seems tricky, staff may hang up, or fob you off, to move on to an easier caller.

Theft: staff may pass your credit card details to friends, or shop with them themselves.

How to steer clear

You can minimise contact with bank and building society call centres by choosing a provider with a good branch service.

Kevin Mountford, of Moneysupermarket.com, the comparison website, says that established names, such as Lloyds TSB, Barclays and HBOS, are best.

Many people now bank online and access customer support by e-mail rather than telephone. Mr Mountford says that First Direct and Birmingham Midshires stand out for standards of online help.

Insurers may also offer online support. Swiftcover, for example, will answer queries by e-mail.

Tips for when you do finally get through

If you intend to make a complaint, be very clear that you want to speak to a manager.

Take names, note the time of the call and how long it lasted.

Complaints in writing are most effective.

Give your phone number. This will enable the manager to trace the call.