If you have ever done a UI testing, gameplay testing is about one or two magnitudes harder. In addition to the inherent complexity of UI testing (e.g. there are exponentially many paths possible), there are simply too many things to test with a lot of subjective criteria for tests. It is common that something feels "wrong" but there are no appropriate metrics to catch that phenomenon.
Large game studios hire tons of quality testers and post-release consumer services to deal with this complexity. It is really amazing to see that human testers can catch many bugs (subjective or not) seemingly impossible to detect. For smaller teams, good luck to you all.
Large game studios hire tons of quality testers and post-release consumer services to deal with this complexity. It is really amazing to see that human testers can catch many bugs (subjective or not) seemingly impossible to detect. For smaller teams, good luck to you all.