Well everyone wants a bargain so discounting a product through coupons will increase traffic but maybe not revenue. To retain that traffic you have to make sure that your business is ready to receive significant customer interest before you proceed as if will be a waste of time and money.
The question is after the coupon has finish is there anything of interest to keep that customer. Service, product and customer care is key.
Never over use coupons as customers will wait until there is an offer, which can decrease revenue but also devalue your goods.
Adding free postage or an extra service to retain your price of products is a good way of doing things.
Offering discounts can be also a good analytic tool to see popularity of products.
Before launching coupon campaign you need to calculate the discount you can offer and still make some profit. If the discount turns out to be pretty decent, then you can offer users coupons. They will sure get you customers.
Coupon codes are good to attract the people and get more traffic and yeah revenue to your sites. People are seeking discounts they will go for it when ever they get one. Particulary online business are vast and there are more customer as well as business. Cusatomer will see all sites and buy from one which give it as less price. Coupons are good way to attract and beat competitors.