Know your rights - that is the key. This doesn't mean you have to turn into a loud, bombastic complainer but simply that you should know what to expect from a company and what they ought to do if something goes wrong.
A few things might help you to know. The first is the Consumer Act of 1976 which relates to the responsibility of a retailer (note the retailer, not the manufacturer) to respond properly to complaints where a product they supply has an inherent fault (ie one which was present at the sale) which becomes apparent in normal use. The fault should appear within 6 months and you then have 6 years to prove your case if the retailer refuses to take responsibility (you need to double check the act for accuracy here!) .
The manufacturer also has a repsonsiblity so if you really get nowhwere with the retailer and feel your complaint is not going to be heard in a hurry, take thematter up with them. A product has to be fit for purpose i.e. a camera should take pictures for a reasonable time before anything goes wrong. If they do not issue a formal guarantee you may have to argue what is reasonable operation but a small claims court will rule on this and it may be worth going to this level if your complaint is over an expensive item.
With any complaint, be clear what you are complaining about and keep it simple and polite. No service provider is going to listen if you are shouting incoherently, no matter how angry you feel. Keep calm and make your complaint politely and to the right person (ask to save you having to explain several times). Most suppliers want to be seen to be providing a good service for the price they charge.
Som retailers will actually check how much you spend with them and settle small complaints even without the manufacter's agreement as they want to keep your business so make good use of the fact you are a regular customer if this is the case..
If the complaint is of a staffing issue such as poor or rude service, ask to speak to a manager and then explain very clearly what you find wrong with their service and also, and this can beimportant, what you expect the company to do about it.
Being heard in terms of volume is easy but being heard in terms of your complaint being understood is actually more important and a supplier is far more likely to listen to you if you keep the facts simple, clear and polite. For example, you go into a hotel and are kept waiting by staff at reception because they are chatting. Don't shout at them, merely ask to see a manager and say that as a valued customer you do not feel it appropriate when you arrive and have to wait for the reception staff to finish their conversation.
Make sure you get names of anyone you speak to regarding a complaint and always put a formal complaint in writing using signed delivery so no-one can argue they did not recieve the letter. Emails get lost 'in systems'and pone calls are 'forgotten' but if you complain by letter any company is obliged to reply in writing.
Complaining so you are heard can be very effective and many companies and suppliers actually appreciate it when a client gives time and effort into an effective complaint which may point out something which is effecting business and is easy to correct (perhaps opening times or lighting for example).
For many companies it is far mroe effective to replace faulty low cost goods than to spend time and trouble arguing the case.
Complaints need not be negative - they can be constructive but you must be clear what you expect for the money you pay, what you want a product or service to provide and exactly how it has failed and the nature of your complaint.
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