As cardinals return to the Sistine Chapel this morning, there are a number of reasons why the second day of voting in a papal conclave is pivotal.
Ultimately, it is when the serious voting begins.
The two most recent popes - Pope Francis and Pope Benedict XVI - were elected on the second day of voting.
Considering the size of the current conclave and the length of time it took for smoke to billow from the Sistine Chapel last night, it is not certain an election will happen today.
Overnight, electors will have reflected on the first vote, which usually leads to more deliberate strategic decisions on day two.
Some cardinals may have gone in yesterday with a 1, 2, 3 preference in their minds.
However, plans like these can change.
Given the time that the process took yesterday, it raises questions as to whether there is uncertainty.
In 2013, during the first vote of Pope Francis's election, it is reported that out of 115 electors, around one in five of them got votes.
There was a scattering of votes in the first round which could have happened in the first round yesterday.
Day two allows for patterns to start to form.
Candidates who received, for example, surprise support in the first round or who performed poorly are reassessed.
It also becomes clearer which cardinals have real support and which do not and discussions among cardinals between ballots often intensify.
It is a transition from exploration to consensus-building.
The voting process can be arduous.
Jorge Bergoglio, later Pope Francis, said he prayed the rosary during the process to pass away the time.
For the men locked into the Sistine Chapel, it is a spiritual exercise.
But make no mistake, cardinals are political animals too and tactical voting will begin.
Over time, votes shift towards a candidate acceptable to a broader group, especially if early favourites fail to reach the two-thirds majority.
If no candidate emerges with strong momentum by the end of day three, perhaps it is time to start worrying.
It can signal divisions or a lack of consensus, which may prolong the conclave.
But this is a message that cardinals are keen to avoid sending to the outside world.
