When I first started out as a webdeveloper I was a 100% for building your own CMS. And I felt like that for a long time. This was mainly because I didn’t like any existing CMS that I tried (Typo3, Mambo, I even didn’t like WordPress back then).
When should you consider building your own CMS?
Some consider building their own CMSes in the following cases:
For more control in terms of customisation & to fit your required purpose (as you cannot modify a code from WordPress or an existing CMS)
If the existing CMSes available do not have the functionality they’re looking for
For a CMS tailor-made to their businesses with features & functionalities they require
For greater security as many popular CMSs are open source. However, paid CMSs that are available but might not necessarily meet business needs.
But, keep things in your mind. The CMS you’ve built could be for your own use or to distribute commercially. If it is to distribute commercially, assess if your CMS is for a niche audience or for the generic audience. If it is for a niche audience, you will need a slightly different marketing approach:
Advertise on Search Engine Marketing (SEM) with banners targeted to the specific industry
Targeted Facebook ads to that industry
Email marketing to a mailing list of those in the niche industry
If you wish to distribute your CMS to a wide audience, you will need to target the pain points of existing CMSs that your CMS solves. The USP of your CMS should be clear. Here are some tips to get the word out:
Your own? Frankly speaking, I see no valid reasons for it since WordPress is still flourishing. You can do a lot with it. Even install a wordpress payment plugin which is in demand for many people. Maybe there are some reasons to develop CMS on your own but it won't be that helpful for the majority of users.