Not all situations which will test your decision-making are as a result of systems failures:
Recent example, flight to an airport in E. Europe with instrument approaches only to one runway.
Forecast/METAR tailwind is right on aircraft limits for landing, but the cloudbase is at/around circling minima. Not enough fuel could be carried to permit significant holding or a second approach.
Do you persist with the ILS and hope the tailwind stays below limits for landing, or break off for a circle and risk losing visual contact?
Either way the 'wrong' decision will result in a diversion (though not a failure in itself), and you recognise the adverse effect such self-imposed task-oriented pressure can have on your thought processes. It would be less stressful if there was only one option (tailwind well out of limits or very low cloud)! Such is life in the LHS.
I always work on the principle that I will have to stand in front of the CPs desk and explain myself. If that looks like it would be difficult to do, then the decision needs revising.