Abdelaziz Bouteflika announced (or actually - it was announced on his behalf) that he will be running for the next presidential elections in Algeria.
This led to massive protests against a senile ruler who is in place for four mandates.
Algeria is a democratic country, they have elections and the candidates people vote for are ultimately elected. If there is such a pressure for Bouteflika not to be reelected, it is enough that people vote for another candidate. Somehow these other candidates gave up once he announced his decision.
If the majority of voters elect him, it means that the majority of the population believes that he will be best suited for that role. This may or may not be the case - bit it does not matter as this is the way democratic elections work.
It looks like ~25% of the population is between 18 and 50 years old, and ~20% above 50. This suggest a rather young population - the one who is currently protesting.
Why are the protesters so sure that Bouteflika will be reelected? Why did the other candidates immediately gave up?