Simple, predictable, and easy to game
The most straightforward way to launch a token is a fixed-price public sale: the project announces a price, opens a sale at a specific time, and anyone can buy in at that price until the allocation runs out. It's easy to explain, easy to build, and easy for participants to reason about, since there's no auction dynamics or timing strategy to think through, you just decide whether the fixed price is worth paying.
That simplicity is also its biggest weakness. When demand exceeds supply, which is the normal case for any sale worth participating in, the sale becomes a race. Whoever gets their transaction confirmed first gets the allocation, and everyone else gets nothing. That race isn't won by whoever cares most about the project or plans to use it longest, it's won by whoever has the fastest infrastructure and the technical sophistication to submit a transaction at exactly the right moment, often by running specialized software that watches for the sale to open and fires immediately.