All missions are a series of skill checks, of varying contextual difficulty and specific skills, the number of checks will also vary - longer missions have more opportunity for error but also cause the biggest impacts.
Missions offer multiple checks to obtain the same goal, for example, a guard could be stabbed to allow passage or a speech check could suffice. This allows for two completely differently trained agents to accomplish the same goal, they just do it in ways that reflects their skills and training.
A failed check isn't the end of a mission either, there will be contextual consequences. For example, failing to pick a lock won't alert the guards, but it will mean the agent needs to spend valuable time trying again or finding the key if they either don't have another lock pick or find the lock is too hard for their skill level(in other word a different skill check is chosen).
Missions offer multiple checks to obtain the same goal, for example, a guard could be stabbed to allow passage or a speech check could suffice. This allows for two completely differently trained agents to accomplish the same goal, they just do it in ways that reflects their skills and training.
A failed check isn't the end of a mission either, there will be contextual consequences. For example, failing to pick a lock won't alert the guards, but it will mean the agent needs to spend valuable time trying again or finding the key if they either don't have another lock pick or find the lock is too hard for their skill level(in other word a different skill check is chosen).