What trade-off results from the leg placement optimized for a grebe's feeding strategy?

Answer

Their legs are set far back, which is excellent for propulsion but makes them clumsy on land

Grebes' legs are set far back on their bodies, a feature excellent for propulsion during underwater pursuit, but this positioning results in them being clumsy when moving on land.

What trade-off results from the leg placement optimized for a grebe's feeding strategy?
foodbirdanimalGrebe