What is the primary purpose of presidential primary elections?

The primary purpose of presidential primary elections is to determine delegates for party conventions. During these primaries, voters in each state choose their preferred candidates, which allows political parties to allocate delegates based on the votes received. These delegates then attend national conventions, where they formally nominate their party's candidate for president. This process is essential in shaping both the party's platform and its nominee, as the outcome of these primaries can significantly influence who will be on the ballot in the general election. The involvement of voters in these early stages also reflects the democratic process within the party system, allowing for grassroots participation in the selection of candidates.