Hind-sight is twenty-twenty. After the fact, one can easily point out where Jefferson Davis made his mistakes and how the Confederacy lost the war. Starting in the West, Davis found himself regretting many of his decisions that would became fateful for the newly created nation.
The first mistake Davis made was in making his friends commanders. One such mistake was with Joseph Johnston as the commander of the western theater of the Confederacy military. Though successful in withdrawals, it became obvious that the lack of offensive moves on Johnston's part hurt the Confederacy. Instead of pushing the initiative when he had the chance, Johnston elected instead to pull back. This left many opportunities unexplored by the South which in turn only allowed the Union to grow stronger. Davis only pulled Johnston from leadership when pushed to do so. If Davis would have pulled Johnston out of command earlier, the South might have had a different result in the West which would in turn have impacted the eastern theater. Add that with other poor choices such as Polk, the western theatre was practically doomed. Davis was too slow in responding to poor performance and let friendship come before leadership.
Davis was one to also try to defend all of the South at once. When added with poor appointee decisions as in Johnston as western theater commander, this was crippling to the Confederacy. The South had limited resources. Davis spread these resources over the entire South instead of pooling them together to protect more vital and strategic locations. This further weakened the Confederacy, giving the Union a more decided edge against them. Davis should have been more deliberate in what areas to defend in the West as well as where to attack.
Third, Davis had trouble focusing on the western theatre. Because he was personally attending to defending the entire South, he could not focus on everything before him. This meant that sections were neglected at times. The western front would find itself the focus of Davis and the military at one point and then practically ignored at others. The time between the Battle of Shiloh and Davis' visit to the West was a period of neglect of the western theatre. Opportunities were again missed.
Davis seemed to have bitten off more than he could chew. Trying to stay loyal to friends at time outweighed loyalty to the Confederacy. He wanted to protect all of the South and was unwilling to let any part go in order to protect the whole. Davis also had his own focus pulled in too many directions. The western theatre had such promise for the South, but it was not appreciated in time.