General fixed-term / fixed-interest specific use cases:
Implementing long trading strategies—for example, borrowing DAI and going long on ETH. But to implement proper trading strategies, we do need to know the cost of capital in advance. See more details in the blog article “Potential of Fixed-Term-Loans in Bullish Market”.
Implementing short trading strategies—borrowing ETH, selling ETH, and buying it back at the lower exchange rate. In this case, we need to know the cost of capital too. See more details in the blog article “Potential of Fixed-Term Loans in Bearish Market”.
Yield farming strategies—borrowing stablecoins and investing them into diverse yield farming products. See more details in the blog article “Yield Farming with Fixed-Term-Loans”
All these use cases need to know the cost of capital in advance. Otherwise, investors would deal with two variable parameters—variable investment return and variable cost of capital—which is rather gambling and not investment anymore.