Casting too hard
A long snood and a powerful cast always end in a bird's nest. Slow down the stroke, keep the bait swinging cleanly and lob the rig out rather than firing it.
Mono snood instead of fluoro
The whole point is invisibility in clear water. Standard mono is visible to spooky bass and wrasse and you'll see the bait pass over without a touch. Use fluorocarbon for the snood, every time.
Lead too heavy
This rig is built for natural movement. A 6 oz grip lead pins everything flat. Use only as much weight as you need to hold position (often 2 to 3 oz), and accept some drift, that's how the bait fishes.
Hook too small
Bass and wrasse have hard mouths and tough lips. A small wire hook bends out under pressure. Use a strong, wide-gape pattern in 2/0 minimum, sharpened before every session.
No rotten bottom
Inshore rough ground takes leads. Without a weak-link, every snag costs you the whole rig. A 10 lb rotten bottom keeps the snood and hook even when the lead is lost.