What Are The Main Differences Of Defining A Control Statically Or Creating It Dynamically On Page Load

I am working on a project which creates controls dynamically for a form in the page_load event, loads in their current values from the database and saves their values (using FindControl) when the user clicks the continue button. When I added a control statically in the .aspx page and followed their same procedure of loading the value in the page load and saving it on the button press I found that the value would not save correctly. It seems that it wouldn't save because the click event fires after the page_load, so the page_load of the post back reverted the value and the user entered value was not saved.

The strange thing is that by changing the control to be dynamically created just as all the other controls on the page and keeping the loading and saving the same it now works. Even though the page load still creates the control with the old database value. It seems like a very fundamental asp .net feature here but i'm just unclear as to what is going on. I suspect it is to do with the timing of creation and maybe when the view state kicks in.