Odoo ERP implementation failures are often blamed on the software, but in many cases the underlying issues are unrealistic timelines, unclear requirements, excessive customization, poor data quality, limited user adoption, or a lack of executive sponsorship. We put together this guide after seeing the same patterns repeated across Odoo ERP projects in different industries. The article looks at common implementation mistakes, how they affect upgrades and long-term maintenance, and practical ways to reduce project risk before and during deployment. I'd be interested to hear from others who have worked on ERP implementations. Which factors have had the biggest impact on project success or failure in your experience? Have you found effective ways to balance customization with keeping the ERP maintainable over time?