Answer :

For - Good products do not need advertising. This can be justified as follows...
If a person buys a product and finds it good, that person will obviously recommend it to another. That person might share it with the other. This way the product does not have to be advertised, which is wasting a lot of money.
When a person buys a product after seeing it on TV, they might think that it is nice. They will go to buy it. But after using it, if they do not find it satisfactory, they will not buy things advertised in TV anymore. So if your product, which is 100 percent good, is being advertised on TV, people will think it is just like the other products, so nobody will buy your product.
Against - Good products need advertising. This can be justified as follows... If you do not advertise your product, which is 100 percent good, it will not gain publicity. So only if someone comes in to a shop and sees your product, they might buy it if they like it. But if you advertise your product, people will get excited and come to a shop with the decision of only buying your product.
Products advertised on TVs and radios are more popular and more bought compared to the products not advertised.