Through IEO you don't need to spend your effort to see the token is being traded because when the pre sale is done the token will be traded on the exchange.

But, when you have a project you need a lot of effort. Like you have to convince the investor that the project will be successful and the token will be traded on the exchange. After that, you have to ask to some exchange to list your project and being traded there and you may need to spend money in it.