That is the most important part nowadays and it has been for quite a while.Rolling out the product and service is not the hard part anymore or having an idea.Everyone does it these days and has an idea, but getting people to use your product or service is the part where 90% of projects fail.
This has also to do with the fact that 90% of the services developed are just not needed.
That is also one of the sad truths, most projects simply don't bring anything that is needed to the table and then when people ask do you have a competition I die inside It simply doesn't matter if you have a competitors if you are not competetive either...