Why is a 3 way handshake not a 2 way?

Related questions

1. What is SSL handshake process?
2. What causes SSL certificate errors?
3. What is SSL handshake explain its main features?
4. What is SSL negotiation?
5. What are handshake signals?
6. How do I setup a 2 way SSL?
7. What is SSL error?
8. What is mutual SSL?
9. What is handshake WIFI?
10. What is a SSL handshake failure?

Tags

1. #sequence
2. #connection
3. #during
4. #again
5. #packet
6. #flags
7. #packets
8. #happen
9. #segment
10. #three
11. #initiation
12. #necessary
13. #synchronize
14. #involved
15. #middle
16. #because
17. #numbers
18. #their
19. #process
20. #handshake
21. #parties
22. #transmission