Why build a custom ERP instead of using SAP, Tally, or an off-the-shelf ERP?
Off-the-shelf ERPs are built for a generic "average" business. Traditional industries like textile or education have workflows, dyeing batch reconciliation, job-work costing, admission pipelines, fee installment logic, that generic modules cannot represent without expensive customization. A custom ERP maps exactly to how you operate, so adoption is faster and data is actually accurate.