Agile of Agile Manifesto fame fails to deliver agility in two primary use cases: diminishing marginal return of team resources and reduced agility with scale. Each of these is reason not to attempt to implement Agile on an enterprise level.
In the case of teams, we need to consider that the Agile Manifesto was penned by top-notch developers with depth and breadth of experience. It’s unlikely that your enterprise is chock full of A-team resources. More likely, you’ve got a couple B-team resources with a bench full of C and D listers. We can’t all be winners. Relatively speaking, your considered A-level resource would not be working for you if s/he could be employed at an A-level company, which you are unlikely to be. I hate to be the messenger, but you probably aren’t all that—hubris and ego aside. Even if for some reason you have an A-level resource, that’s one. That’s a LeBron James with the support of a plethora of semi-pros that leaves you with one team, but it’s almost certainly not an all-star team except in your mind. This LeBron team may end up winning, but it’s on the strength of one or two individuals, and you’re unlikely to field another team at this level. It’s all maths.
Besides this or in addition, you face a scalability problem. The larger the structure, the greater the need for hierarchies, which by the very nature become more rigid with scale. So, not only are your teams subject to sequentially lower quality—I know you love all of your children equally—, they face the prospect of inertia due to infrastructural constraints.
Add to this regulatory and compliance burdens as well as release schedule constraints, and you’ve all but sapped out any last vestiges of agility. Borrowing the notion of degrees of freedom from the domain of statistics, you’ve got little wiggle room. And wiggle room is analogous to agility.
In the end, it’s not your fault. The deck is stacked against you. Your only blame is for not recognising these limitations and thinking you can deliver an enterprise-level Agile implementation. Methodologies such as SAFe and LeSS are leaches that prey on this lack of insight. Even the notion of agility in Scrum of Scrums is a pipe dream.
It’s not that the level of organisation and coordination of these scaling paradigms isn’t warranted. It’s just that they come at a trade-off of the promised agility. Moreover, they create an extra layer of administrative overhead over simply coordinating these management activities outside of a so-called Agile framework. Best to jettison the Agile pretence and run with some revised program portfolio approach. If on a project level, it makes sense to deliver it Agile-y, then by all means, to it. Just don’t try to square-peg all of your projects into round Agile holes.