Were the agreement a hire purchase agreement, with exactly the same consequences as to cost, the finance company would have to disclose the exorbitant interest rate. No sensible person would sign to take on such an agreement. They would see immediately that the interest rate makes the good'ol Barclaycard look like a model of financial probity and common sense. There is also the absence of transparency about what is the actual price of the machine itself as sold to the finance company. You can not, typically, discover just what was the purchase price, and compare it with what you might have paid in cash from a third party.
Similar considerations apply to the costs of repair.
The third problem is that the contractual relationships and responsibilities are thrown up in the air, and lie where they fall, in a rather untidy heap. The person who bought it does not repair it, and any warranty was given by somebody else to that finance company, and you can't sue on it. Repair and maintenance obligations can quickly falter when any one part of the contracting team falls by the way-side. We are sure that there will be many people who take on leasing agreements, and are happy with them. There must be.