There are and will continue to be cloud outages. Those outages might happen at a local level because your internet is disrupted either by physical means (a digger cuts your broadband) or because of cyberattacks. But the big vendors have outages too and because, we are all increasingly reliant on their services, when the cloud stops, work stops. Few companies have backup systems to turn to in this situation. So long as cloud vendors keep outages to a minimum, then users will probably consider that using the cloud is more reliable than home-grown apps. But if outages become widespread, that opinion might change.