There are any number of issues that a state would have to consider as it made the transition from authoritarianism to a more democratic system. Let us look at a few considerations, advantages, and disadvantages to such a move.
Perhaps the biggest advantage comes in the long term. In the long term, a more democratic system is more likely to be stable than a traditional authoritarian system. Authoritarian systems are inherently unstable because they are based on a foundation of coercion and fear. Democratic systems are more stable because they are based on the consent of the people. This means that people in a democratic society are not waiting for their chance to overthrow their government in the way that people in an authoritarian system are.
However, a move towards democracy is likely to create instability in the short term. The people of the country will be used to being oppressed and will want rapid change. It will be very hard for the regime to give them just a little bit of change. We saw this in the fall of the Soviet Union. The leadership of the USSR wanted to open the political system just a little bit but they were unable to keep the people from pushing for more radical reforms. This is why China’s Communist Party is unwilling to do much in the way of political reforms. They fear that if they give an inch, the people will take a mile. This is a real concern facing any country that tries to make the transition to greater democracy.
One thing to consider is whether the country has built in divisions that will make it harder to democratize properly. A strong democracy cannot be based on what can be called “identity politics.” In other words, democracies will struggle if people vote based on who they are rather than on what their beliefs are. Often, countries that have tried to democratize have had problems because various groups in their populace (usually different ethnic groups) simply band together and try to use the democratic process to take power for themselves. We can see this to a great degree in Iraq, where Sunnis, Shiites, and Kurds are generally forming blocs based on religion or ethnicity instead of forming parties based on ideology. The more ethnic and religious splits there are in a country, the harder it will be to democratize.
Finally, the country will need to consider how it will deal with members of the old regime. As the country moves towards democracy, there will be many people who will want to hold members of the old regime accountable for their actions during the time of authoritarianism. This is dangerous for a country because there will be strong forces on either side of the issue. If the regime was oppressive, people will be very motivated to punish those who oppressed them in the past. At the same time, those people who supported the regime will be very reluctant to allow the prosecution of those who led the country. This was, for example, a major issue that South Africa had to face as it went away from its apartheid regime.
All of these are things that a country must consider if it is contemplating a move away from authoritarianism and towards democracy.