A group — sometimes organised through a private messaging channel — quietly accumulates a cheap, low-liquidity token, then simultaneously begins promoting it heavily across social media, forums, and messaging groups, often with claims of insider information or an imminent breakthrough.
The coordinated buying and hype drive the price up rapidly, creating visible momentum that attracts outside buyers who fear missing out on the rise, buying in without knowing the rally was manufactured.
Once the price peaks, the organising group sells ("dumps") their holdings into that outside demand, collapsing the price. The outside buyers who bought during the hype are left holding a token that's now worth a fraction of what they paid.