I straightened my type 4c hair why is it frizzy?

I straightened my hair and it feels great. Like surprisingly soft. However it looks frizzy not dry, just frizzy. Like water touched your hair after or something which it didn't. It doesnt keep a curl when I curl it with a curling iron it just unravels after a while and just looks frizzy.  How can I control this or fix it? Before I straightened it I had it deep conditioned so I don't think it's dry and I made sure to use a heat protectant cause I don't want to damage my hair. I included a pict for observation 

2 Answers

There could be multiple reasons why: you need a trim, you need a better quality flat iron, you need to straighten in smaller sections, you need to blow-dry is smaller section, you live in a high humidity climate, etc. 
If you wash your hair every day, then that's what is soaking the moisture out of your hair and damaging your ends, so you need to try washing your hair every other day and apply a good moisturizer and leave in conditioner to help your hair maintain having healthy looking ends