Giving away free samples can be an excellent way to gain new lifelong customers. The condition in which giving out free samples works is the following:
1. Make sure you have a product people NEED to buy over and over again (like toilet paper is a good example. Everyone needs it and you will pretty much keep buying tp the rest of your life)
2. Make sure you send freebies to qualified customers. Don't just send em to anyone who asks. Identify the type of person most likely to be a real customer. Those are the ones that should get the freebies.
3. The best way to make the freebie thing work is to make sure you send them enough to use more than one time. For example, I got a free sample of shaving cream that I really like. There's so much in this one little bottle that I've been using it for about a month. Now I'm hooked. Next time I go to buy shaving cream, I'm gonna opt to buy the one I'm soooo familiar with. If I only had one sample that lasted one shave, I would not be hooked on it enough for that to sway my decision.
Companies that do really well with freebies are personal care products. Shaving cream, lotions, shampoos, etc. make sure your freebie isn't something they can use forever. Then there would be no need to buy from you.
By the way, if you have a product that does not meet the above criteria, I have advice for you. Just let me know if you want me to get into details.