There's a surprising amount of persuasion, negotiation, and coalition-building in order to find the votes to grant cert or hold a majority. It's interesting to see how the interpersonal dynamics among the Justices influence decisions.
An example of this is looking for unanimous decisions to send a strong message, whether it is for school desegregation:
> Since 1954, the Court had always been unanimous in school cases, its strong commands to desegregate joined by every member. For fifteen years, the Justices had agreed that it was essential to let the South know that not a single Justice believed in anything less than full desegregation.
or to reject Nixon's executive privilege claims in Watergate [2]:
> The Nixon challenge had to be met in the strongest way possible. An eight-signature opinion would do it [...] The country would benefit from such a show of strength now.
These decisions required significant reconciliation between the original ideas of the Justices. They don't operate in a vacuum of law study. The Muhammad Ali draft dodging case [3] also demonstrates this, where a 4-4 deadlock is turned into a unanimous 8-0 decision centered around a technical error which would not set precedent - the book describes Burger as considering that "it might be interpreted as a racist vote" if he dissented.
Like the link, I am also curious about why these delays have occurred, especially the most recent one. Wildly speculating, maybe the Court does not want to appear too politically activist in this moment; or maybe the members are trying to find consensus for their preferred outcome before granting cert at all. One other option, though I hope it's not this one:
> [Stevens] said, it was "pointless" to grant cert only to have the majority reaffirm its well-known view [regarding Liles v Oregon, an obscenity case].
[1] https://en.wikipedia.org/wiki/The_Brethren_(Woodward_and_Arm...
[2] https://en.wikipedia.org/wiki/United_States_v._Nixon
[3] https://en.wikipedia.org/wiki/Clay_v._United_States#Opinion_...