When possible, always upload the original photo when placing an order.
You want to avoid using images taken from social media sites, or from email accounts, because these are usually compressed to make sharing quicker, which decreases the file size and often results in pixelation and a decrease in image quality.
Submitting the original photo, in the highest resolution possible, will also allow you more printing options later on, since it's bigger in size.
When comparing these two images, you notice the original file is much sharper with more detail. The compressed version is very pixelated, making the skin, cap and background look blotchy. In addition to image degradation, the image taken from social media is much smaller than the original, which limits the size it can be printed.
For more information on resolution and file size, please refer to the Help Center section Ordering Tips - "Upload a High Resolution Photo".