This is a common question with a simple answer.
It’s no different from devotion to anyone or anything else.
Love Bollywood or Hollywood or cricket or football? Why is that? Because of constant exposure.
What do we see on Instagram or Twitter or TV? What do we read about in the newspaper?
As we keep reading more and more about the glories of celebrities and sports stars, that only becomes a virtuous reinforcing loop.
The same thing is applicable to God as well. The more we read about Him and His leelas through various stories and scriptures, the more our devotion will become stronger!