The Confederacy wanted to win foreign support. Therefore it had to choose leaders who would appear sane, moderate, and responsible. Radical "Fire-eaters" like Rhett and Yancey had much power and influence, but those who were chosen to head the Confederacy, Davis and Stephens, would at least have to appear to be reluctant secessionists. Perhaps they were. But two further caveats are necessary. 1) Few politicians would give up their seats until their state had seceeded. Therefore, they'd have to at least appear to be committed to working out a compromise up to the last moment. They'd have to have clean hands, in case secession didn't come through. 2) The real debate in the cotton states wasn't between secession and union but between independent secession and cooperative action between the slave states. Was South Carolina or Mississippi going to go it alone, or were they going to form a league or union or new nation with other seceeding states. Many who were hesitant about seceeding wanted to see if other states would join theirs. Some may even have been working behind the scenes to make sure that if secession came it would be successful.
Northern unionists didn't understand this. They took such hesitation about secession for real commitment to the union and saw hope for preserving the nation in it. Hesitation -- indeed opposition to secession -- was more real in the Upper South, at least up until Sumter, but was likewise overrated by Northerners. It wouldn't survive the outbreak of hostilities. In the North, what we read now as a debate about letting rebel states go or holding them in by force was often a debate about whether to make concessions to the slave states. That was the real question for many concerned. Many unionists wanted to stand firm and resist concessions, rather than to fight and conquer or to simply let go and let the country fall apart. Events overtook this debate. Before Sumter war was one cloudy possibility among others, after it, there appeared to be no alternative to fighting. Just as Northerners read Southern hesitancy as implying more unionist sentiment than it did, so Southerners read the Northern position as implying more acceptance of secession and unwillingness to fight than was the case.
But also, reluctance is one of the great elements of political persuasion, especially in 19th century American politics. If Caesar wants the crown, he is a tyrant. If Augustus has it thrust upon him by the Senate and people, he can't resist it. Washington became President in part because he didn't want it, and since then statesmen always took care not to appear to want office or power too much. Every candidate had to maintain that his party's nomination came to him unsought and unsolicited. That's why nominees didn't even go to the conventions in those days. Jefferson Davis was not a secessionist militant, but that didn't mean he was devoted to preserving the Union. Whether he appeared to hold back because of loyalty, prudence, caution or concealed ambition would be hard to resolve.