Answer: Coalition begins for good reason
Explanation: Coalition could be explained as a unique formation of more than one individual, group or body who share common interest coming together in other to jointly address issues a specific problem.
In the scenario above, the principle of coalition exhibited by the three employees is that coalitions are formed for good reasons. These three employees aim to address the incessant complained level led against their colleagues by sharing ideas and coming up with good solution in other to foster better relationship between the bank employees and customers in future.