When asked what stops them from safely and regularly deploying every change into production environments - everybody seems to have their own reasons. Organizational, cultural, historical, technical, contractual.. Some go as far into denial as saying : "Oh, we don't need continuous delivery. In fact most companies out there don't really need it." But the underlying reason is of course the lack of confidence. Nobody wants to be the culprit for a system outage. According to a number of industry surveys the average cost of one hour of downtime is around 75000 USD. There's a lot at stake! So instead we choose to move slower, to add controlled handoffs and build home-grown guardrails. To hire more Ops engineers and call them SRE to feel more secure. Rarely discussing the price of establishing and maintaining all of these over time.
Engineers who've experienced true CD can't really fathom any other way of delivering software. As @giltayar puts it "CD ... is a total game changer. It changes how you perceive software development and delivering features... I did CD and EVERYTHING about how I developed changed. It was magical."