I'm looking for your biggest non-obvious insight / "aha" that you discovered when preparing to launch (prior to bringing employees on board and/or scaling).
Focus on the factors under your control. When you start out, the easiest factor to control is your expenses. Stay lean and you'll make profitability much easier to achieve. Starting is great but until profits are fueling your growth don't overthink what you're doing, keep your energies focused on that.
Experience will save you a lot of heartache. I'm learning so much at the startup I'm currently working at, just by witnessing how decisions are made, what tradeoffs need to be made, etc.
These will all be invaluable if I ever start my own company, and yet I never realized any of this until I accidentally ended up working for somebody else.