First we need to consider what is a "Bond?" In times past people entered contracts, usually to pay off debts but frequently to pay for a sea passage, bonding them to work for an employer for a specific time to discharge the debt. Such bondage contracts were transferrable so the employer could in fact "sell" the labour of a bonded labourer to another employer. This is a true Contract of Bondage. Being similar to slavery in some ways, bondage contracts are immoral which is why they are legally unenforceable in the same way as, for example, gambling debts. The problem with modern "Bonding" is that the contracts we call Bonds are not technically any such thing, they are actually training contracts. The deal is written as an agreement for the trainee to pay for training with charges waived if the trainee continues in the employer's service for a specific period after completing the training. The difference between this and a true Bond may be small but it is significant. The employer cannot sell the bond to a third party. No sign, no course; leave before the agreed period and the fee becomes payable. Simple, there's nothing immoral about that.
We once had a contract employee who was sent to Boeing for training, but somehow he slipped through the net and departed without signing a "Bond". The company asked him to sign when he returned from Boeing but he refused. At the end of his contract soon afterwards, the company tried to deduct the training costs from his end of service benefit but he took the matter to court and won without going to trial. This was a special situation, since no contract actually existed, the company was unable to enforce payment and he received his end of service benefit in full.
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Through difficulties to the cinema