What is smurfing in League of Legends?

Have you ever came across a highly skilled player on a low rank? Smurfing in League of Legends is a big issue, but why do players do it?

League of Legends Accounts for Sale - Buy LoL Smurf Accounts

How to spot a smurf account in League of Legends

Just wondering if smurfing is a problem? My team got rocked and flamed me : r/leagueoflegends

Is Riot even trying to deal with smurf's anymore? I understand smurf que is apparently a thing, but it's OBVIOUSLY not working. In 2 different games today I had a combined FOUR

Smurf (Dmitri Ivanov) - Leaguepedia

Online Gaming: The Effect of Smurfing and How to Handle it.

Announcing the smurf detection and search feature, by André Pimenta

Why can people just smurf, acknowledge they are smurfing and not get banned. : r/leagueoflegends

Is Smurfing Safe In League Of Legends - Eloking