If DeFi is viewed as an emerging mature financial system, then fixed interest rates are almost an unavoidable step. In traditional finance, the premise for large-scale capital inflows has never been high returns, but predictability. Fixed borrowing costs mean that companies can plan long-term, institutions can manage durations, and individuals can clearly define their cash flow boundaries. These principles also apply on-chain, but until now, there has been a lack of suitable tools. @TermMaxFi is doing something simple yet challenging: locking in the time dimension, interest rate levels, and risk boundaries for both borrowers and lenders in advance, so participants know what they are taking on before entering. This makes DeFi no longer just suitable for short-term speculation, but capable of supporting more serious capital uses. When fixed interest rates are combined with structured products, risk itself becomes a modular element that can be designed and combined. For the industry, this is a crucial step from speculation toward building financial infrastructure.