I USED to take my vases out of the kiln as soon as they were cool to touch. Big mistake! They would develop hairline cracks within days. Now I wait for the full cycle, even if it takes hours. The difference in strength is HUGE. No more wasted work!
It's disrespectful to the craft and the artists who dedicate their lives to it. I've had to correct more assumptions than I can count... and it's exhausting. Just once, I'd like someone to ask about the technique or the history.
A quick scrub isn't enough to prevent glass from sticking.