Why does "ungroup" not actually ungroup things?

[SashaHoneypalm]

So "group" is easy enough. You select a certain number of objects, you group them together, and Inkscape treats them as a unit. They move around together, you can't select only one of them unless you use the Edit Paths By Nodes tool, and you can't layer outside objects in between the components.
So "ungroup" or, maybe "pop selected objects out of group", should, well, ungroup whatever you've selected. It should be free to roam the page unyoked, to be raised or lowered completely independently of its former compatriots.
But it doesn't do that. When I select a component and ungroup it, it stays stubbornly grouped. As far as I can tell- which, admittedly, doesn't mean much- the effect of "ungroup" and "pop selected objects out of group" are jack and squat.
So what does ungroup actually do, and how do I removed objects from a group like I want to?

[Moini]

Things can be grouped multiple times. Have you tried ungrouping multiple times?

[Lazur]

I'm using a cad program where you can select an object within a group and when ungrouping the selected object it is split from the group.
However inkscape is more strict about the group structure.

Instead of that, you can enter the group, select the object, cut it (Ctrl+X), exit group (Ctrl+Backspace) and paste in position (Ctrl+Alt+W).

[brynn]

It sounds like it might be time for you to discover the status bar!  When the Selection tool is enabled, anything that's selected will be identified in the status bar.  And the status bar gives different info, depending on which tool is enabled.  Aside from being helpful during drawing or editing, it's really helpful for learning on your own.  It will help you to learn the terminology, and once you start to have the right terminology, the manual starts to make more sense.  (Help menu > Inkscape manual)

So as Moini suggested, perhaps you have some nested groups.  The status bar will tell you.  If you somehow have one object in a group selected, ungrouping will not break it out of its group or ungroup its group.  You need to deselect it, and locate its whole group.  Once the whole group is selected, you can ungroup it. 

Or it's possible you have some other kind of object.  Only a group responds to being ungrouped.  If you have a compound path, for example, or a clone, or anything else except for a group, it won't resond to ungrouping.

If you still can't get where you're going, you can always share the SVG file with us, and we can explain what's happening.

Fyi, besides using the Node tool to select an individual object in a group, you can do it with the Selection tool, while holding Ctrl key. 

Or you can enter a group by double-clicking on any object of a group.  I tend not to suggest that for beginners, because it can get confusing.  But you might like to use it.  After you enter the group, you can select the individual members of the group (with Selection tool).  To exit the group, you need to click on some object that's outside the group.

[SashaHoneypalm]

Things can be grouped multiple times. Have you tried ungrouping multiple times?

So you're saying that if I group Objects A and B and then add C and then add D, if I want to remove A I have to ungroup it three times in a row?

[SashaHoneypalm]

It sounds like it might be time for you to discover the status bar!  When the Selection tool is enabled, anything that's selected will be identified in the status bar.  And the status bar gives different info, depending on which tool is enabled.  Aside from being helpful during drawing or editing, it's really helpful for learning on your own.  It will help you to learn the terminology, and once you start to have the right terminology, the manual starts to make more sense.  (Help menu > Inkscape manual)

So as Moini suggested, perhaps you have some nested groups.  The status bar will tell you.  If you somehow have one object in a group selected, ungrouping will not break it out of its group or ungroup its group.  You need to deselect it, and locate its whole group.  Once the whole group is selected, you can ungroup it. 

Or it's possible you have some other kind of object.  Only a group responds to being ungrouped.  If you have a compound path, for example, or a clone, or anything else except for a group, it won't resond to ungrouping.

If you still can't get where you're going, you can always share the SVG file with us, and we can explain what's happening.

Fyi, besides using the Node tool to select an individual object in a group, you can do it with the Selection tool, while holding Ctrl key. 

Or you can enter a group by double-clicking on any object of a group.  I tend not to suggest that for beginners, because it can get confusing.  But you might like to use it.  After you enter the group, you can select the individual members of the group (with Selection tool).  To exit the group, you need to click on some object that's outside the group.

Ok, I'll play around with it in the next day or so and see what happens.

[Moini]

You don't need to ungroup to cut an object from a group. But you can, if you desire to resolve the group.

[ronburk]

I got a lot happier with groups after I started leaving the "Objects" (Object->Objects...) window open on a second monitor.  Status line is well and good, but the window can make the whole hierarchy visual. This also encouraged me to be more aggressive about naming groups. Many times, some behavior I would have previously labelled as "weird" was made clear by looking at the tree in the Objects window. It also serves as a visual reminder of how closely related groups and layers are.

[Moini]

They are the same. Only Inkscape promotes some groups to layers, by adding a special label to them. To all other programs, Inkscape's layers are nothing but SVG groups.