It's hard to answer this because we don't know where you are on your journey.
If you're super early on, go from zero to one. Build one feature, get one customer, etc. If you're further along and are getting customers through a working marketing funnel, I'd focus on making that as efficient as possible and reducing CAC. I'd also measure the onboarding sequence and time to value.
I'd also take a look at your current metrics and set goals in relation to them. Let's say you're getting ten customers a week. Set a goal of increasing to 15 customers a week in the next X weeks/months, 20 customers, and a stretch goal of 30 customers.
If you're only getting ten customers a week and you set yourself a goal of 100,000 customers in X months, you'll break your business. Work backwards from 100,000 to see how much effort, growth, money, people, etc you'd need to achieve that.
Ambitious goals are good but so are S.M.A.R.T. goals where the R stands for realistic.
Building things, nobody wants or is willing to pay for. Basically, there is no market need.
Not solving a real problem for a specific ICP.