If you've read the accepted answer and the link and still don't get it (like I did see my PS bellow) then here it is in black and white:
this keybinding will take you to the workspace having a name starting with 1
bindsym $mod+1 workspace number 1
whereas this will take you to the workspace named "1" (nothing more nothing less)
bindsym $mod+1 workspace 1
There's a good chance you have the later syntax in your config.
So, to give you the big picture, if you want to work with named workspaces you must:
define a keybinding like this in your config (I chose $mod+n from reName because $mod+r was allready taken for Resize):
bindsym $mod+n exec i3-input -F 'rename workspace to "%s"' -P 'New name for this workspace: ' (unimportant details regarding this command in notes [1],[2])
make sure that your config has bindings with the number keyword for switching to your workspaces (i.e. lines like this: bindsym $mod+1 workspace number 1 and not like this: bindsym $mod+1 workspace 1)
Notes:
1: the user guide omits the double quotes around %s but they are needed (names with spaces will be truncated if you don't use them -- maybe other bad things will happen).
2: super-geeks can also directly execute commands like this: i3-msg 'rename workspace 1 to "1: foo"' in order to rename a workspace.
PS
I can't tell you how bad I felt after trying and retrying for many minutes to rename and access my workspaces with $mod+<num>. Either it was a silly moment or the guide and the syntax begs for misunderstandings. In (my very biased opinion at the moment) it's more of the later :). It seems that this particular topic (working with named workspaces) of the otherwise excellent user guide is full of traps:
- $mod+r is presented as an example both for
resizing clients and for renaming
workspaces
- the keybinding command that uses i3-input omits " around %s. As a result renaming to anything containing spaces fails. The examples always have spaces in the names.
- the topic of this thread