Because her was there for her during the whole pregnancy
Because even though they didn't end together, they loved each other very much.
'Sometimes you can love each other deeply, but not get that happily ever after.'
Because they both dreamed romantically about each other.
Because when he thought she was pregnant, he asked for her hand in marriage.
Because when she thought he asked to marry her she said yes without hesitation.
Because if he had Rachel, that would stop him from sleeping around all the time.
Because she made him love her without even trying.
Because their friendship remained strong through everything.
Because they were the first two with the secret about Monica&Chandler.
Because when Mr. Treeger made Rachel cry, Joey wanted to teach him a lesson.
Because on their first date, he bought her favourite flowers.
Because they both fell for each others moves on their date.
Because she was excited when Joey lift her. 9x20.
Because he thought about them a lot of times and not once did he say no.
Because it took him over 30 years to fall in love, and it was with her.

#1 Because He Really Loved Her
#2: She is his first true love, and the only one he only really loved.
#3: "Joey. Honey what would I do without you?" "You don’t have to worry about that..."
#4: Because Rachel kicked the woman who kept punching Joey!
http://www.fanforum.com/f88/cobras-%...kick-63079785/
http://www.fanforum.com/f88/cobras-%...ppen-63128108/
Cobras [Joey&Rachel] #7: Because "they're not really good enough for you, and you deserve the best."
Cobras [Joey&Rachel] #8: Because their friendship remained strong through everything.
http://www.fanforum.com/f88/cobras-%...joey-63172215/