This is because you created all the task folders so you are the owner and you can see them all or you are either the Key Account Holder or an Admin user on the account.
It is possible to set up task folders and not share these with other users so that they are not made 'global' as shown below:
If however you want ALL your users to see your folders then you will need to let us know and we will select them for you - example below shows Tom the user and we have ticked his Global Folders so that the rest of the team can see them:
This is how the shared/global folders work.
Please note however if certain members of staff - other users, can only see certain ones, this means there is a restriction applied.
If you wish have different set ups then please send over the details to our Support Desk and we can then advise you.