Mission to the moon. Plasma and roll ups are often cut down to a simple comparison of old versus new, but that framing misses the real trade off. Both are scaling methods that move activity off the base layer, yet they make very different assumptions about what must live on chain and what can safely live elsewhere. Only commitments and occasional proofs are posted to the base layer, which keeps fees low and throughput high. The cost of that efficiency is difficulty around exits and user safety. If operators misbehave or go offline, users may need to actively exit to protect funds. That puts more responsibility on users and infrastructure like watchers. Plasma works best when applications have predictable behavior and when users value low cost over instant guarantees. Roll ups take the opposite approach. They post transaction data on chain, which makes state reconstruction and verification simple. This design gives stronger security and simpler user experience because funds are always recoverable directly from on chain data. The trade off is cost. Data availability is costly, and as usage grows, roll ups inherit some of the base layer’s congestion and fee pressure. Roll ups scale execution well, but they do not escape the economics of data. What people rarely explain clearly is that this is not a linear upgrade path. Roll ups did not replace Plasma because they are strictly better. They replaced Plasma in many stories because the ecosystem prioritised safety, composability, and developer simplicity over maximum cost efficiency. That was a rational choice for general purpose systems, especially DeFi, where trust assumptions must be minimal. @Plasma #Plasma $XPL