The best teams I've built were never the most talented on paper.
When you're handed the job of building a team, the instinct is to collect the best players. The strongest CVs, the deepest experience, the person who can do the hardest thing in the room. I tried to build teams that way early on, and it taught me I was solving the wrong problem.
A team is not a list of names. I've watched a group of brilliant people deliver less than a group of solid ones, because the brilliant group never gelled. Everyone optimised their own piece and nobody minded the gaps between them. How a team works together, and what it produces as a unit, matters more than how good any individual is on their own.
It also has to have range. Can it handle a sprint, the short intense push when something genuinely has to ship? And can it hold a marathon pace for years without burning anyone out? A team that can only do one of those is fragile.
Then there's the part people miss most. A team is never finished. People grow, people change, people come and go. The team you built last year is not the team you have today, so you keep adapting it, reshaping how it works and who carries what as the people in it change.
Building a team is not a one-shot decision. It's a constant process. The names on it turn over, but the team carries on, and keeping it good is work that never really stops.