Well I do rather agree, but as a consultancy I'm biased.

But let's do some math. Say it's 4 months (because who has uninterrupted time), a senior rate of $1000/day. 20 days a month, so 80 days, is an $80k outlay. That's assuming you can get the skills (because AWS et al like to hire these kinds of engineers).

Say one wants a 3 year payback, that is $2,200/month savings you need. Which seems highly achievable given some of the cloud spends I've seen, and that I think an 80-90% reduction in cloud spend is a good ballpark.

The appeal of a consultancy is that we'll remove the up-front investment, provide the skills, de-risk the whole endeavour, even put engineers within your team, but you'll _only_ save 50%.

The latter option is much more appealing in terms of hiring, risk, and cash-flow. But if your company has the skills, the cash, and the risk tolerance then maybe the former approach is best.

EDIT: I actually think the(/our) consultancy option is a really good idea for startups. Their infrastructure ends up being slightly over-built to start with, but very quickly they end up saving a lot of money, and they also get DevOps staffing without having to hire for it. Moreover, the DevOps resource available to them scales with their compute needs. (also we offer 2x the amount of DevOps days for startups for the first year to help them get up and running).