Lindsay's name gag

Lindsay is shown to have a problem with remembering names, as evident throughout the series. If the person was a close friend of Lindsay or even her boyfriend, more often than not, she would get their name wrong, sometimes more than once.

Overview
Lindsay is clearly one of the most unintelligent contestants in the game and it even shows when she doesn't know their name. While this running gag was seen in nearly every Total Drama Island episode, the running gag was seen less and less in future seasons, as Lindsay trying to remember Tyler seemed to be used in more episodes.

Alejandro
Lindsay confuses Tyler's name with Alejandro in Walk Like an Egyptian - Part 1, Alejandro's first episode.

Beth
Despite being B.F.F.s and in an alliance with Beth, Lindsay called her Belle in Paintball Deer Hunter.

Chris
At first, Lindsay could not remember Chris' name at all and later called him Kyle. She would call him Chip later on in No Pain, No Game.

Duncan
After winning the final challenge in X-Treme Torture, Duncan was called Doug.

Eva
Lindsay may have simply mispronounced her name as "Ava,” as that is a commonly-accepted pronunciation of the name; just not in Eva's case. She called her this in No Pain, No Game. She has correctly pronounced Eva's name before, particularly in The Big Sleep.

Gwen
Gwen was referred as Greta in That's Off the Chain!, even though Lindsay called her by her proper name in the past, as well as after this episode.

Heather
Even though Lindsay correctly remembered Heather's name throughout Total Drama Island, Heather was called her Hannah in the final episode of the season.

Leshawna
Lindsay had various names for Leshawna, the more commonly-used Lequisha, as well as Lafawnduh in Not So Happy Campers - Part 2 and Haute Camp-ture. However, she did correctly pronounce Leshawna's name twice when she accidentally "voted" for her later on in Haute Camp-ture.

Owen
Owen was called Omar in Beach Blanket Bogus and The Chefshank Redemption, despite always getting his name right in the previous season.

Trent
Lindsay called Trent, Todd in Who Can You Trust?, despite getting his name right in Up the Creek, which was prior to that episode. She would also confuse his name with Tyler's in Beach Blanket Bogus.

Tyler
Despite being Lindsay's boyfriend, Lindsay usually didn't remember who Tyler was or what his name was. In Phobia Factor confessional at the end of the episode, Lindsay called him Taylor, but quickly corrected herself.

Haute Camp-ture started a new running gag in which she also had no idea who Tyler was. Lindsay asked Eva, an eskimo, and even bunny who he was. This carried over into Total Drama Action, as she confused Trent for Tyler in Beach Blanket Bogus. In One Million Bucks, B.C., she called him Tyson, and was quickly corrected. She even blanked on his name in Walk Like An Egyptian - Part 1 while Alejandro was flirting with her. She also confused Tyler for Noah in Anything Yukon Do, I Can Do Better and she called him Dave in Broadway, Baby!.

In Slap Slap Revolution, she called him Darrell, until she finally remembered who he was later in the episode. However, in Can't Help Falling in Louvre, Lindsay said she couldn't wait to see Tyler and remembered his name. However, before the challenge, Lindsay almost forgets about Tyler when she doesn't recognize what he looks like, but Tyler reminds her who he is.

When Tyler fell on the floor in Aftermath Aftermayham, Lindsay got worried about him and remembered his name. Leshawna believed that Lindsay would have remembered his name and won five bucks from Trent because of it.

She also called Tyler many different names in her Total Drama World Tour biography, including Todd, Terry, Ted, Owen and Sebastian.

Trivia

 * Lindsay forgot someone's name a total of thirteen times in Total Drama Island, four times in Total Drama Action and three times in Total Drama World Tour for twenty times in the series.
 * Lindsay didn't know Tyler's name a total of seven times, the most for any character and didn't know who he was or if he was in the competition or not a total of three times.