All matricies are symmetric because the patterns were symmetric. Similarly, pattern two can be verified to be stable.
All networks amplify and complete the weak, incomplete pattern input.
All other networks could use inhibitory connections to correct the error and eliminate the extraneous unit activation. In this example, the patterns overlap, making them difficult for some nets to learn to differentiate. The Hebb network fails to differentiate because it lacks inhibition. No oscillation, but the network is not correctly recalled. Oscillations are avoided with asynchronous updates, but the results can be variable, due randomly picking the unit to update.