Yes. Even if your K-ETA has been approved, you may still be asked additional questions during immigration inspection, such as your travel purpose, length of stay, accommodation information, return ticket, or onward travel plan.
K-ETA approval does not automatically guarantee entry into Korea, so it is best to check that your passport details and actual travel plan match your application information before departure.
If you are preparing to travel to Korea, please apply for Keta Korea before departure.