There are managed dedicated servers and unmanaged dedicated servers. With managed servers, your host does the maintenance and takes care of the day-to-day management of the server. With an unamanaged server, however, it is your responsibility to keep the server opratational.
The web host’s responsibility in an unamanaged server situation is to simply provide the hardware for storage, security, and bandwidth.
If you don’t have access to an IT department or professionals with the knowledge and background to manage a server environment then you are best going with a managed server. But you can save money with the unamanaged server since you are already paying your staff to run your computer networks. It is an additional responsibility for your team, but less expense.
One of the biggest downsides to an unmanaged dedicated server is if you have a problem with your web host and you have to change providers then it’s a big hassle to move all of your data from that host’s servers to a new web host. That’s why owning the dedicated server is best, if you can manage that.