Yes and, it depends. Last time I was procuring racks of servers, it was about a 6 week lead time, sometimes more. So yeah, you have to do a lot more capacity p

Yes and, it depends. Last time I was procuring racks of servers, it was about a 6 week lead time, sometimes more. So yeah, you have to do a lot more capacity planning, and probably keep capacity in reserve for things that are unexpected. I've had to go around to every engineering team and try to get them to tell me how much gear they might need in the next 1-2 quarters. They rarely know, so it's a lot of guess work. So in a situation with a quickly growing product, that grows in an unpredictable way. Or a really new product where you just have no idea what the adoption is going to look like. Then yeah, getting those new instances right now is really really important. At Segment we very often needed more instances in a huge hurry due to some customer load spike. And sometimes AWS ran out of the instances we needed in the region we were in. So we had to get creative to use other instance types. Also the cloud provider pricing structure heavily incentives you to actually do some capacity planning. On AWS, Savings Plan gives you huge savings. But if your workload is fairly predictable, then this on demand benefit isn't nearly as compelling and at the right scale, it makes sense to start buying servers to put in your own datacenter.