Final answer:
The static friction force fs = μs N signifies that it has reached its maximum limit; this is the highest force that static friction can exert to resist motion before an object begins to slide.
Step-by-step explanation:
When fs = μs N, the static friction force has reached its maximum limit. Static friction is a force that resists the start of sliding motion between two surfaces in contact. It is proportional to the normal force, which is perpendicular to the surfaces in contact, and is calculated by the equation fs ≤ μs N, with fs(max) = μs N. Once the applied force exceeds this maximum static friction force, the object will start to move. This indicates that the maximum value of static friction has been reached and any additional force will cause the object to overcome this static friction and start moving.