No flying without wings.

Achievement depends on having the essential abilities, resources, or conditions that make it possible. One cannot reasonably expect a result while lacking what is fundamentally required to produce it.

The saying can caution against ambitions detached from practical preparation. It does not condemn aspiration itself; rather, it stresses that goals need a workable basis before they can be fulfilled. The particular limitation it points to depends on the situation.

Use it to emphasize a necessary prerequisite for success, especially when someone expects an outcome without the skills, support, tools, or preparation needed to attain it. Because the image is broad, the precise practical limitation should be clear from the situation.