"Luck usually sides with the more determined party."
George Hourani Arab Seafaring
Why should this be so- because it is easily observable in everyday life? I suspect that the more determined you are the more open your are to any option. You mimic therefore extreme flexibility. A lack of determination might be characterised as an unwillingness to pursue certain options. The more flexible you are the more options you have- and therefore the 'luckier' you appear. Determination can suggest a certain fanaticism. But it could also be, in the absence of any observably pushy behaviour, the pursuit of extreme flexibility backed up solely by an unwillingness to give up.