Sometimes clips, adjustment layers etc. just disappear

Only asking because this happens to me frequently… I am well aware of holding down shift when I delete or ~. Here's a good example of what I'm talking about… If I delete the highlighted voiceover pieces in the timeline, the adjustment layer also disappears. There is no connection between those voiceover pieces and that adjustment layer… I can individually delete them while holding the shift key and that works fine but if I try to do them all at once the adjustment layer disappears while holding shift or ~.