John's breakdown is accurate. I want to add a few points from the NVOCC/consolidator side that shippers often don't consider.
Cargo co-mingling risk in LCL: When your furniture shares a container with industrial chemicals, electronics, or food products, there's a small but real risk of odour contamination or moisture damage if an adjacent shipment leaks or has humidity issues. Good consolidators segregate cargo types, but it's worth asking your forwarder which CFS they use and whether they separate cargo categories.
CFS cut-off times: LCL has strict cut-off deadlines at the CFS — typically 3–5 days before vessel departure. Missing the cut means waiting for the next sailing. FCL gives you more flexibility since the container comes to your supplier's door.
Insurance consideration: For furniture worth, say, $15,000–$20,000, the additional handling in LCL means you should definitely buy cargo insurance. The extra premium of $80–120 is well worth it. FCL insurance is also recommended, but the risk profile is lower.
When to consider FCL anyway: If your furniture pieces are very large (sofas, beds, wardrobes), some may be considered "long cargo" or exceed CFS handling limits, which can create complications for LCL. Check the individual piece dimensions with your forwarder.