The God of fate is Zeus Moiragetes. He has three helpers, all goddesses known as the Moirai.
Clotho, who when a mortal is conceived, attempts to spin out a thread of life, and usually succeeds in the task.
Lachesis, then pulls out the thread to its maximum length, taking into account the strengths and weaknesses of each individual mortal.
Aisa is able to cut the thread short after consideration of the actions of each mortal.
There is inherent randomness in the process, which only intensifies as the paths of mortals cross, enabling them to exert influence on each other. The influences may be welcomed or rejected but often affect the ways mortals behave or what they find themselves able to achieve.
Aisa’s decision is not, therefore, an inflexible fate. Zeus, if he chooses, has the power of overriding Aisa’s decision where it can be seen that the mortal still has the potential for good, despite the prevailing circumstances.