Shite analogy, but sometimes people like to build the Lego model themselves, rather than just play with the assembled set.
There's no question most of us are posting out of hope and blind faith here, but I think we're clinging on to the idea that he has created a real bond between the supporters and the club here. Of course he might do that at Dundee as well, or he might guide you to a couple of 8th-placed finishes, get binned, and never get the 'big' move he craves.
I'm not having a go at Dundee here, becasue we have killed off more managers' careers than probably any other club, but Paul Hartley was basically Jack Ross a few seasons ago. Tipped for big things. He did amazing things for you, but probably stayed too long and now doesn't seem to be getting linked with anything. Rewind, say, two years, you could well have seen PH being linked with a vacant job at Aberdeen, for example.
Of course, and I'm talking round in circles here, perhaps JR's ambition is such that that would never happen. Perhaps he'd use Dundee's decent budget to achieve quickly in a short space of time, and then move on just as you've started to love him...
(I know Hartley hates us, but I'd take him at SMP if it came down to it... )