The Bond films continually are confronted with the same problem: the need to top themselves.
That need merely might be caused by the studio who wants to make more money on the next film. Or by audiences who expect every new Bond film to deliver more excitement.
In any event, this problem seems to manifest itself in every fourth film of an actor´s tenure.
The first film always has to meet the challenge of introducing a new actor - but with Connery, Lazenby, Moore, Dalton, Brosnan and Craig, the first film can be considered a success. At that point, everybody is highly motivated to establish the new tone.
The second film can build on that and often experiments. This can deepen the impact of the actor (Connery, Brosnan, Craig) or cause problems with the audience (Moore, Dalton).
The third film can feature the actor in his most assured portrayal (Connery, Moore, Craig) or falter (Brosnan) - in both cases the "we have to top everything"-syndrome already can be felt but still is kept under control.
It´s the fourth film that naturally has the tendency to set itself apart from the previous ones, going for MORE and ending up not hitting the mark completely. Connery´s THUNDERBALL has a lot going for it - but the excess stifles it. Moore´s MOONRAKER is great fun - but the excess turns it into parody, like Brosnan´s DIE ANOTHER DAY does.
SPECTRE walks the tightrope between seriousness and excess, and it might be the first one within the series´ history to not fall down on either side.
Still, one can feel its wobbly legs.
The Connery era went even further with the fifth film while Moore´s tenure scaled down. Will the Craig era - should he return - go back to its lean beginnings or do a YOU ONLY LIVE TWICE (the film - not the novel, although...)?