Why take time to start installing exe file? (sized-> 600 mb,published from Adobe Flash CC using Air 19.0.0.241 for Desktop)

Hi,

I published exe file from Adobe flash cc using Air for Desktop.

exe file contains 31  numbers of file.

when user click on exe,after around 2 minutes ,open "Application Install" dialog..
Can you please tell me know why its take that much time to start installing exe?
Thanks