Neglecting software security updates can lead to significant vulnerabilities. Outdated software is prone to exploits that hackers can use to access sensitive data, steal information, or disrupt services. These vulnerabilities can result in costly data breaches, compromised user trust, and potential legal ramifications. Additionally, failing to perform updates can lead to software incompatibility issues that hinder performance and functionality. Therefore, regularly applying security patches and updates is critical for maintaining a secure and efficient software environment.