while creating a component
there appear a dialog box , on the bottom
we see “replace the selection with component”
what this means ?
When “Replace selection with component” is check marked…
The selected entities are replaced with the new component.
And
The newly created component definition also appears in the Components Browser - In Model panel.
When “Replace selection with component” is not check marked…
The selected entities simply remain as they were before creating the new component.
And
The newly created component definition appears only in the Components Browser - In Model panel.
Note: If the selection is attached to other geometry, then it automatically turns off when you create a component - always check that it’s checked/un-checked as you expect.
(I have been caught out too many times by this - I now create a group [ctrl-G] and turn the group into a component [R-click].)