It's only natural to go toward what you're more familiar with. Those without any particular pull often seem at a loss for what to start with. In which case they'd try to go for whatever was considered "easy", instead of going by necessity. Though there are too many individuals involved to make a clear case for it. And the spirits themselves, are individuals with varying methods. Twila and Nala are more eager while Hyt is not, Eferin and Sona are more selective, and so forth.