Building with WordPress IS website development. There are WordPress naysayers on the internet that will try to convince people otherwise, but it totally is. Some of those individuals might argue that unless you are building from scratch, it is not truly development. Others might say the WordPress does not do a good job or is too heavy with unnecessary resources and so on and so forth.
The reason those arguments are false is because of another WordPress myth. That myth is that building on WordPress is purely a two step process; install it then fill it with content. While it certainly is possible to do only those two things, developing a website with WordPress, as with any other methods, is much more complicated than that. Leaving out those complexities for the sake of rapid deployment is ridiculously the wrong way to do it. Those that claim they can build a WordPress website in a day or so are more than likely doing it wrong.
It’s really the little things. And there are a lot of little things. Careful attention to those details whether building with WordPress or another method is very important.
Because of this, if you want your website developed in a few days I am not the guy for the job. Doing so might just be setting your up for failure and disappointment.