The short answer
Routes can impose minimum or maximum amounts because of liquidity, provider requirements, operational limits, or the economics of small transactions.
ONESWAP LEARN
Crypto Bridge Minimums and Limits Explained.
Why some routes have minimum amounts, maximums or liquidity constraints.
How it works
A minimum may prevent a transfer from being uneconomical after gas and fees. A maximum can protect liquidity or reflect a provider's current capacity.
Why it matters
These limits can change by token and network pair. Always check the live quote rather than assuming a route supports every amount.
Practical takeaway
If a route rejects your amount, try a supported route or a different amount only when it still fits your needs. Never split transactions blindly because each transaction can add another layer of cost.