Quinn got involved in a traffic collision while texting behind the wheel in the last episode of the Fox programme, though spoiler pictures from filming have shown her alive and in a wheelchair.
Speaking about her hopes for the plot, Agron said that her character's "fairly sad" fate should help raise awareness of the dangers of texting and driving.
"I told [Ryan], 'I think it's a great thing and we should do it'," she explained to TV Guide. "We discussed the levels of the story, 'Should she die?'
"Ultimately, we weighed it and what we came up with is a story that might make some people fairly sad, but the takeaway is worth it... It's very smart of us to touch on this problem because there needs to be an awareness."
Agron claimed that she has changed her own habits since the storyline, even pulling over her car to take a call recently instead of fumbling with a hands-free device.
"It's the joke around set that if I'm even walking and texting I'll be in trouble," she added. "Don't do that, Dianna!' they all say. 'What would Quinn think?'"
Glee returns in the US tonight (April 10) at 8/7c on Fox. UK viewers can see the episode Thursday at 9pm on Sky1.
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