The most common question I get from prospective clients and blog followers migrating from file shares to SharePoint is whether or not they should be creating SharePoint sites for their department/projects/client folders or maintain them all in folders in a single document library, just like on the network drive. With this post, I would like to provide an answer to this question and explain why sites instead of folders make sense in SharePoint.
Never, ever try to replicate your file share in SharePoint
Reason 1: Why bother with SharePoint?
If you are thinking of using SharePoint as a file share, why bother with SharePoint? Seriously? It is like buying an airplane and using it to drive to a supermarket to buy groceries. You paid for functionality, you might as well use it! See my other related post on this topic.
Reason 2: Scalability
When you dump it all into 1 document library, you are looking for trouble. At some point, your document library will become unmanageable (if it is not already) as it will grow in size as you accumulate more projects, clients, etc. You probably heard about the infamous 5,000 view Item limit, if not, you can read about it here.
With SharePoint Sites (1 for each department or project or client), it is very unlikely you will encounter often (if at all) the above limit.
Reason 3: Other web parts
You probably care mostly about files and folders at the moment, but SharePoint Sites allow you to add and display other, non-document content to a project or department via additional web parts. Custom Lists, Calendars, People Web Part, embedding videos and Power BI reports are just a few examples. When you just have a single site with a single document library with ten levels of subfolders, you live a boring life, dude.
Reason 4: Cleaner security management
When you have folders and need to have unique security, like a need to hide a folder, you would need to start breaking permissions inheritance for various folders. It is @#$% messy! Managing security at a site level is considered best practice and is much easier on everyone, especially the site owners.
So whether you need to create a new department or project or client repository, create a new SharePoint site first! Do not create just another folder. And with Office 365 Groups overtaking your Intranet, you will have a separate site (site collection to be precise) anyway!