This is the 2361st most frequent Polish word.
wystąpiły
"Occurred" or "appeared."
The word 'wystąpiły' is used here to indicate the occurrence of a situation (technical problems) that arose during an event.
Wystąpiły problemy techniczne podczas prezentacji.
Technical issues occurred during the presentation.
The word 'wystąpiły' is used in this context to describe that someone made an appearance or performed at an event, specifically a music festival.
Wystąpiły jako goście specjalni na festiwalu muzycznym.
They performed as special guests at the music festival.
Here, the word 'wystąpiły' refers to the emergence or presence of mistakes within a process or analysis.