What it actually is
A bill of lading does three jobs at once. It is a receipt for the goods, it is the contract of carriage, and on the original form it is a document of title. That third job is the one that catches people out, because it means whoever holds the paper controls the cargo.
With an original bill, the carrier releases the container to the party who surrenders one of the three signed originals at destination. No paper, no release, however clearly you can prove the goods are yours.
The three forms
Original is the safe choice when you are shipping to a buyer who has not paid yet, or when a bank sits between you on a letter of credit. Control of the goods stays with the paper until the money moves.
Express release, sometimes called telex release, means no paper travels. The carrier releases to the named consignee on identity alone. It is fast, and it is right when you are shipping to yourself or to a customer with credit terms you are comfortable with.
A seaway bill is a non-negotiable receipt. Same speed as express, and it cannot be transferred to somebody else in transit, which is a feature if you never intend it to be.
The failure that keeps happening
Originals are issued at origin and couriered to the buyer. The vessel takes 14 days. The courier takes four. Then the buyer files the pack, the accounts department is on leave, and a container sits on a wharf accruing storage while three signed pieces of paper sit in an envelope on somebody desk.
If the cargo is paid for and the relationship is settled, ask for express release at booking. Changing after the originals are printed means surrendering all three back to the carrier, which takes longer than the sailing does.