I think it depends on what your website requires. Personally, I prefer managing my websites for budget/cost reasons. You can always look for resources if you're not familiar with a certain service/host. You'll definitely learn along the way.
I prefer to manage my own website. For people who does not know the technicalities of website, they can still manage it but hire someone to do the work for them.
if you want to spread your business online it is better to hire someone to manage your site rather managing your self if you want quick and better results.
I think this is a question best asked tou yourself. Can you manage your own website or do you need someone else to do it for you? It's different with every business, and there is really no universal answer.
It all boils down between time, money and expertise. If you have the time and expertise, its better to manage it yourself but if you don't, have someone else manage it for you but be sure you have at least the basic knowledge of your website.