Aries- They forgot  to tell you something earlier and they just remembered

Taurus-They  wanted to talk about life and the universe

Gemini- They need to talk about something serious

Cancer- They're lonely 

Leo- They need help with something

Virgo- They're bored

Libra- no one else is texting them

Scorpio-  They're *cough cough* C O R N I E S 

Sagittarius- They need to confess something

Capricorn- They need reassurance that they aren't a terrible person

Aquarius- To check up on you

Pisces- Because they love you and want to make sure you're doing ok