Being an inventor can be a very financially rewarding job, if you manage to invent something new that is in demand. Some people are constantly inventing new things in the hope that just one of their ideas will become a success.
In order to make a successful invention you need to think carefully about the product or service you want to create. The best products or services offer an easy solution to a common problem. If you think about pest control for example, lots of people wanted a way to get rid of a rat or a mouse without having to kill it so humane traps were invented. They are easy to use and effective and therefore in demand. Some products such as a humane trap can easily be replicated so although you may be able to patent some of it, it is likely that other companies may well design a similar product. For this reason you need to ensure that you are able to meet demand should your product hit it off otherwise you may find that your competitors quickly launch their product too and steal a lot of your custom. Be sure to patent your idea before starting to sell it.