Promotion decisions rest heavily on evidence from demanding projects. Those projects are handed out through a process that is almost never written down.
The assignment is a risk transfer
A stretch project is one where the person assigned is not yet demonstrably capable of it. The manager is accepting some probability of failure in exchange for development.
Because the manager carries that risk, the decision is personal and cautious. It is made about someone the manager believes will ask for help before the project derails.
Trust of that specific kind is built through prior contact, which is why proximity to the decision-maker matters more than the formal record does.
Availability is read as a proxy for commitment
Stretch work often arrives with short notice and unclear boundaries. Managers weigh who can absorb it now, and that assessment is frequently made without asking.
Assumptions about caregiving responsibilities, travel willingness or working hours can remove someone from consideration before any conversation happens.
The exclusion is invisible to the person excluded, because there is no posting, no decline and no record that the opportunity existed.
Glue work absorbs the same capacity
Organizations rely on coordination work: onboarding, documentation, meeting facilitation, keeping a project's pieces aligned. It is essential and it is rarely counted at promotion.
People who do this work well are asked to do more of it, and the time it consumes is the same time a stretch assignment would require.
Being reliable at necessary invisible work can therefore reduce access to visible work, which is the opposite of what the effort deserves.
Visibility is a property of the project, not the effort
Two equally difficult projects differ enormously in career value depending on who sees the outcome and whether the contribution is attributable to an individual.
Work reported to senior leadership, tied to a revenue or risk outcome, or presented by the person who did it carries weight that internal cleanup does not.
Choosing between offered projects on this basis is legitimate, and asking who will see the result is a reasonable question to raise when accepting one.
Asking changes the distribution
Because allocation is informal, stating an interest in specific kinds of work puts a name into a decision that otherwise runs on assumption.
The request is more effective when it is concrete: a named project type, a named skill to build, rather than a general wish for growth.
Managers largely cannot act on ambitions they have not heard, and they are rarely tracking who has been given which opportunities across a team.