'Grounded' means the plane could not take off. It was on the ground and must remain there. Landing a deal (or a fish) is like landing a plane. A human acts t

'Grounded' means the plane could not take off. It was on the ground and must remain there. Landing a deal (or a fish) is like landing a plane. A human acts to cause a desired outcome. Unlike forcing a pilot to involuntarily land a plane, the perspective of the fish as involuntarily being forced to land is not a necessary inference for this use of 'land'. Geez, language can be subtle.