I believe in doing what you love, even if you can't do it full time. If you can only write part-time (like me) then just do it! However, writing is more than just typing on your computer. There is more marketing, advertising involved than actual writing. It will take up a lot of your time and energy. It is truly a calling and for those who will dedicate their lives to it. So, before you dip your toe into the writing pool, make sure you can immerse yourself in it, first.