Many people tend to think that commissioning a custom-built system is better than buying off-the-shelf software, because most off-the-shelf ERP programs come with operational limitations. This leads to the idea that hiring a programmer to write an ERP program is better than choosing an off-the-shelf software vendor — because you get the system you want, the price is cheaper, and you own the system yourself. But the disadvantages of writing the program yourself outweigh those of an off-the-shelf system, as follows:

Risk of the contractor abandoning the project
Budget overruns, and the system not supporting tax requirements
The system not conforming to ERP standards
Not having enough knowledge to design a system that can operate over the long term

Each point is detailed below.

Risk of the contractor abandoning the project — Because building any system yourself requires someone to design the system and someone to write it, and most highly experienced developers come with very expensive labor costs. If the business owner’s requirements exceed the agreement, or the system is too complex, there is a risk that the contractor will abandon the project if they no longer wish to continue developing it. Some contractors stall the work until the system can never be successfully completed.
Budget overruns, and the system not supporting tax requirements — With an off-the-shelf system, the Implementer plans in advance how the work will proceed, allowing the business owner to control the budget. But when you commission a custom program, what happens is that the client is not skilled in designing an ERP system and focuses on working according to the organization’s whims, resulting in the system never being finished. The development cost keeps ballooning according to the users’ demands. A custom-written system usually does not support tax requirements, and developing that part further only makes the budget even less worthwhile than before.
The system not conforming to ERP standards — Because an ERP system requires experts to design, if the business owner does not have enough knowledge, the system will not be correct according to ERP principles. Most business owners are not particularly concerned about whether the system conforms to ERP principles, with the result that the system you commissioned cannot avoid manual work in order to close the books, and cannot file taxes according to the correct standards.
Not having enough knowledge to design a system that can operate over the long term — Following on from the previous point, insufficient knowledge of building ERP systems ultimately means the self-developed system cannot keep up with the organization’s growth, and you cannot avoid having to find an experienced ERP developer to come in and set up the system for the organization.

So, the claim that commissioning a custom ERP system is better than an off-the-shelf one can be summarized as having more disadvantages than choosing an off-the-shelf ERP vendor, as follows:

Risk of the contractor abandoning the project
Budget overruns, and the system not supporting tax requirements
The system not conforming to ERP standards
Not having enough knowledge to design a system that can operate over the long term

Off-the-shelf software comes from experts who understand system design, which is why off-the-shelf ERP programs usually succeed in setting up the system more than commissioned custom systems.

PlanetOne ERP is an off-the-shelf ERP system with high flexibility, supports tax requirements, is certified by the Revenue Department as Type B, has high expertise, is a large-scale ERP system developed by Thai people, supports organizations of every size, is customizable, and supports high growth.

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