Unfortunately people leaving DF because someone has spoken up about being new to an instance is something that can happen but is ultimately beyond their control (No lying doesn’t really stop this as they’ll just do it to the next person).
There’s nothing wrong with nor should anyone be ashamed of being new to content
Keep in mind I’m also not suggesting that people have to enter every instance with a giant flag over their heads saying “I’ve never been here” I get that some people don’t want to be put on the spot like that, and its fine, once again I feel the Duty Finder is a learning environment.
The Issue arises when a specific question is posed to the party and either nobody responds or they flat out lie about it.
“Has everyone done this fight before?”
If a person lies in response to or says nothing to this at all then they are causing a bigger problem than the one caused by those who ditch the DF, this is further amplified if they are playing a VITAL role in the party composition (See: TANK / HEALER)
If you are a healer or a tank and enter Titan and have no idea what you’re supposed to do, say nothing, and proceed to die the entire fight, you are now a liability to the 7 other people who want to do the content as bad as you do.
Your refusal to be open and honest about the situation is essentially robbing the rest of the group of a fighting chance.
There’s a reason that the DF gives us 90 minutes on most encounters that average groups of appropriately geared players can clear in half the time or less (in some cases even a fraction of the time) It’s there so that if things need to be explained or attempted multiple times you have the leeway to do so, you are essentially provided with TIME TO LEARN.
And as for experience?
What experience are you getting if you enter say... Titan, die early in the fight, and get carried to a win, especially if no mechanics were explained to you.
None.
After the initial glow of completing your Relic fades off (it will eventually) and you decide to go do Titan again whether it be for yourself or to help someone else you will now have no idea how to perform and will be no better off than your first attempt.
This is why it’s an issue.