The main reason people encounter sync failures is a slow Internet connection.
Why does your Internet speed matter?
Think of it like this:
At any given time, there are many people trying to upload photos to our cloud, and at the same time we have limited amounts of bandwidth to allow these photos through.
When you start to sync your device up to the cloud - Spex's servers allocate a certain amount of time they will keep the door open for your photos to go in.
If you can't get them all synced up in time, you'll get a sync failure. Here's what to do.