Airdrop need just follow, just like follow the various bounty campaigns. When there is an option of 100% success, you can spend your time on it. In all other cases, pass by.
no one guarantees a 100% successful bounty or airdrop campaign. if there is maybe you will get very little from airdrop. my advice is don't choose airdrop with the payment of their new token project. try to search for airdrop with top-up token payments that have been traded such as XRP, ETH, XLM, we see some airdrops succeeding and indeed pay for platforms that are already running and developing.
Most of them don't and wouldn't have value. Even those airdrops that seem to have a very good roadmap and a useable project can end up stagnant for long time wouldn't get listed at all. Of course it wouldn't require much to acquire some free tokens, but as for me, it kinda gets confusing when you're holding lot of tokens that mostly will just use up space in my wallet. Airdrops aren't like years before when one can actually be lucky enough to really get free money.