Elections give the power to the people and enable them to choose their leaders who make decisions on their behalf. Other forms of government like dictatorships do not have this option.
Democracy is based on all people having the same rights and having the country ruled by the people. Because of this, elections are essential. During elections, people have the opportunity to choose who they would like to represent them. The leaders that are chosen then have the opportunity to vote and institute rules that represent what the people would have selected.
Without elections, democracy isn't based on the wants and needs of the people. It turns into another type of government where decisions are made by one person or a group of person based on their own motivating factors.