You need to have not only a working product, but also a developed community. Therefore, it is important to attract new people to the project and develop its ecosystem.
Now there is a lot of competition among cryptocurrency projects, so airdrops play a big role, as they help to create and support a community of users.
For any project, liquidity is important, and in order to have good liquidity, you need to have a large community and airdrop is a great opportunity to increase the community.
Airdrop certainly helps to attract attention to the project, advertising and promotion are also important for any project.