The planning gap
Nobody plans a crowded pipeline. It builds up one reasonable Go at a time.
In Stage-Gate, a Go is not applause. It commits people, budget and time to the next stage, and that is the strength of the model: gatekeepers decide Go, Kill, Hold or Recycle, and the resources follow the decision. What is hard to see in the gate meeting is the cost of a Go across the rest of the pipeline. If this project gets the formulation team, which other project waits? If it gets the test lab, which launch moves?
When nobody can answer, the default is to say Go to everything that passes. Stage-Gate portfolio management aims for value, balance, strategic alignment and the right number of projects for the resources available. That last goal is the hardest to keep. The same people also support launched products, fix quality issues and help sales. That work never appears in the pipeline, yet it uses the capacity, and every extra project slows the rest down.
Strategic buckets help leaders make forced choices first: how much effort goes to platforms, new products, improvements and maintenance, so projects compete within their bucket rather than against everything at once. The hard part is translation. Buckets are set in money, while bottlenecks are in people. A bucket can be fully funded and still unable to start its top project, because the lab is booked.