Selflessness or Nishkamta is a very important point in Bhakti or Devotion. Generally people who perform Bhakti are not Nishkaam i.e. their devotion is not devoid of material desires. People pray to God for attainment of material objects-fame, wealth, son, good job etc. In many famous temples, people make big donations.
Why? To get their wish or ‘mannat’ fulfilled. Why should there be a ‘mannat’? We are supposed to abandon love of material possessions to love God whole-heartedly. Instead we pray to God to get more material pleasures! Isn’t this shear insanity? Who would ask for shoes standing in a sweet shop? If he does, wouldn’t he be considered insane.
God is the ocean of bliss. And you are asking Him for material gratifications, which will give you nothing other than misery. You are asking for misery standing at the doorsteps of personified bliss.