Every time i browse the web. Or switch between browsing and a game. Or using the device as a remote for the Apple TV. Everything keeps reloading all the time. Not to mention the intermittent crashing of apps due to low memory.
Lack of ram made the iPad unusable for me, constant reloading of tabs all day due to the system not being able to store web pages on ram. It's similar with the iPhone, maybe not as impactful, but still an important factor.