Might be a non-answer, but I think this really depends on how much leverage you have in pulling engineering + product culture levers. In my experience, you nee

Might be a non-answer, but I think this really depends on how much leverage you have in pulling engineering + product culture levers. In my experience, you need to first define a small set of north star metrics that lead to the promised land, which could be years, if not a decade away. Ideally, this should not be more than 3 so there's focus in the long term. If you define this well, everybody will understand the significance of it and be aligned to hit those objectives. Any increase, exponential or not, is progress the team should feel proud of. This is 80% of the "selling" for long time scale projects. Once you've done that, all other initiatives should focus on improving only these metrics. Generally speaking, very aggressive milestones and keeping that momentum going, while not punishing teams for missing targets will move the needle faster than the other way round.