I manage my own social media but do bulk work. I schedule everything a month at least beforehand - my blogs I have done until March and have had them ready since November.
It's all about being clear what you want to say, the message you want to get across, knowing some time (aka life) saving tools and you don't have to rely on others! :) 

I outsource the mundane jobs that I don't have time to do.  So, I have a girl who does four hours a day setting up all my posts, and responding as my PA. 
 

I run multiple accounts for myself and my several businesses. I typically do everything myself, and almost exclusively manually. It may sound more time intensive, but I personally respond and actively engage my followers. I don't honestly believe that someone else could successfully mimic my style (also I don't know that I'd want people responding for me or as me).

I go for less volume of posts with more meaningful content. I'd rather cut through the noise then create more of it. I do use several tools to help assist in graphics, motion graphics and audio content creation. But I am all about embodying the "Social" part of social media.

My team manages and monitors our social media accounts. We leverage the latest social media management platforms and automation tools to make things easier for us. We also plan a content calendar several months in advance to give us time for client work.

Unless you're skilled or passionate to learn about Social Media Marketing it can be more cost effective and save you time to have a professional provide Social Media Management as a service.