Hi Vaibhav,
Technical explanation for why the get methods are called after .htm page would be :
As you can see that in .htm page we pass the XML which finally decides which all the attributes would be available on UI .
So once the system finds all the attributes which will be visible on UI then it starts to get the data from BOL/Genil(getter method) for those attributes and display them on UI. You can also see that getter method would be called for only those attributes which we made available in our configuration on UI.
.htm page only decides the layout of UI(attributes available on UI) and getter method is actually responsible to show the data in the Attributes.
Hope it helps.
Thanks
Kumar