Explanations for conformity are supported by research. Asch found many of his participants went along with the wrong answer because other people did and they were afraid of disapproval (NSI). This is a strength of the theory because it shows NSI is an explanation for at least some conformity behaviour.
A limitation of the NSI explanation is that it does not account for behaviour in all individuals.
Some research shows that NSI doesn't affect everyone's behaviour in the same way. E.g, people who care less about being liked aren't as affected by ISI. However, people who have a great need for this are described as nAffiliators.
This is a limitation as it doesn't account for behaviour in all individuals so it may not be a valid explanation.