Dust Jackets

It can seem to be a bit of a mystery as to why some books got dust jackets and not others. Some are obviously a way to shift old stock but others are film tie-ins.
    
   
You Only Live Twice You ONly Live Twice
PAN X434 from 1965
Cover Artist Raymond Hawkey Style
 
You ONly Live Twice
Dust Jacket for PAN X434 from 1966
Jacket Photo Film Tie-in
    
You ONly Live Twice You ONly Live Twice
PAN X434 from 1966
Cover Photo Film Tie-in
   
   
David Copperfield  David Copperfield 
PAN E5 from 1967
Cover Artist John Raynes 
 
David Copperfield
Dust Jacket for 0330 400055 from 1970
Jacket Photo Film Tie-in
    
   
Full Circle Full Circle
PAN T45 1968
Cover Artist ?
 
Full Circle
Dust Jacket for PAN 0330 300458
Jacket Artist Glenn Steward
 
Full Circle Full Circle
PAN 0330 300458 1969
Cover Artist Glenn Steward
 
   
Eagle Day Eagle Day
PAN 0330 021052 from 1988
Cover Artist David Etheridge
   
Eagle Day
Dust Jacket for PAN 0330 021052
Jacket Artist Glenn Steward
  
Eagle Day Eagle Dat
PAN 0330 021052 from 1969
Cover Artist Glenn Steward