Page "Locus of control" Paragraph 21

Additional research led to the hypothesis that typical expectancy shifts were displayed more often by those who attributed their outcomes to ability, whereas those who displayed atypical expectancy were more likely to attribute their outcomes to chance.

This was interpreted that people could be divided into those who attribute to ability ( an internal cause ) versus those who attribute to luck ( an external cause ).

Bernard Weiner argued that rather than ability-versus-luck, locus may relate to whether attributions are made to stable or unstable causes.