According to a 2016 survey of CIOs, digital strategists and technology directors by Cloudonomic, the biggest challenges to the implementation of cloud services are legacy systems and compliance/security risks. So it seems likely that the list of enterprises opting for an entirely cloud-based infrastructure will be short, and consist of startups with little or no legacy infrastructure or applications to take into account
That said, the economics of cloud make sense for most enterprises, even for those handling very sensitive data as they will be running less sensitive operations, such as back-office, marketing or productivity, which they are likely to be more suitable for deployment in the cloud.
So the solution is to build a form of hybrid cloud, so that applications run where it makes the most sense, depending on issues such as economic and regulatory constraints, as well as the need to amortise legacy infrastructure, among others.
Hybrid cloud deployments will be fluid. As Niels Bohr said: "It is difficult to make predictions, especially about the future". So the status quo with respect to to the location of applications will change over time, of course, as the enterprise pivots to pursue new lines of business - and as increasing numbers of LOB managers grow to accept that the cloud is now an appropriate location for their applications and data.
For example, managed services remains one of the fastest growth areas within the cloud, showing that cloud applications are continuing to evolve and to become more complex. So as cloud services evolve and become richer, the scope for moving applications into the cloud is likely to increase.
The right hybrid cloud implementation - or perhaps more correctly, set of implementations - will allow the business to switch between dedicated resources, to move applications from public to private infrastructure and back again, as the application requirements change. All that said, however, the hybrid cloud model does offer the key advantages of providing the economic benefits of cloud adoption for those applications where it is appropriate, and it allows the enterprise to make that cloud-wards move at its own pace.
Wherever the applications reside, the key to a successful implementation will remain the ability to control and manage the infrastructure in a seamless manner.
Challenges are plentiful, not least the afore-mentioned issues of security and compliance, internal inertia, and the scarcity of relevant skillsets. So the need for trusted partners to help configure, deploy and manage a hybrid infrastructure is likely to increase, as is the need for consultancy to make the case for implementation.
That said, the business case is likely to win the day, with the key benefit of hybrid cloud conferring the ability to be flexible and agile, and to innovate as the market demands, enabling the ability to try out new models without the risk of upfront investments in infrastructure that may prove to be either unnecessary or incorrectly specified.
So hybrid is the future - but there's nothing inevitable about it. It is up to the enterprise to make the case, to decide where and how to deploy its applications, and to carve its own path to the future.