Why is the coin still falling after falling below the issue price?

1. Some currencies fall as soon as they go online, fall below the issue price, and are still falling. What is the reason for the continuous decline?

2. Some currencies fell as soon as they were launched, then fell and rose, then rose and fell, and finally fell below the issue price and continued to fall. What is the reason?

3. Some currencies rise as soon as they go online, then fall, fall and rise, rise and then fall, and finally fall below the issue price and continue to fall. What is the reason?

Who can help me to answer this seriously?