If Sandhyavandanam is not performed, sin will occur. Moksha is attained only when that sin is gone. As long as that sin remains, one cannot attain Moksha. Perumal Himself will provide a way for the sin to be removed. That is, He will create an opportunity for you to perform the necessary atonement (Prayaschitta). He will give punishment (shiksha). By making one experience that punishment, later He will grant Moksha. Important Note: Do not always link everything to Moksha. It is said that if one does not perform Sandhyavandanam, tells lies, or drinks alcohol, sin will accrue. Please do not link whether Moksha will be attained or not to each of these actions. The fact that Sharanagati (surrender) leads to Moksha is a separate matter. A human must live as a human. A Brahmin must live as a Brahmin. It is unreasonable to ask if someone who lies, harms others, does wrong things, and does not perform Sandhyavandanam will still get Moksha. Therefore, do not link these two things. We say again: first, a human must be a human and a Brahmin must be a Brahmin. Ask only by linking that. Do not link random things to Moksha. Those who ask if there is an obstacle to Moksha are often looking for a way to escape from performing Sandhyavandanam. Such indirect motives are dangerous, so avoid them. A person should be good, respect the Shastras, and follow their Svadharma (personal duty); this is the general rule. Moksha is a special rule. Do not confuse the two. One should not give excuses for not performing Sandhyavandanam.