Why do you use alt="" in the image tag ?
The alt attribute provides alternative information for an image if a user for some reason cannot view it (because of slow connection, an error in the src attribute, or if the user uses a screen reader). http://www.w3schools.com/tags/att_img_alt.asp
If the image does not load because of the internet connection or the file does not exist, the text inside the alt will show up.
the alt attribute is used to display a text in the event that the image cannot be displayed in the browser
Use alt="" if the image is only for decoration