underestimate

To make too low an estimate of the quantity, degree, or worth of.

To consider (someone) to be less capable or effective than is actually the case.

An estimate that is or proves to be too low.

To estimate at too low a rate; not to value sufficiently.

An estimate or valuing at too low a rate.

To set too low a value on; to estimate below the truth.

The act of underestimating; too low an estimate.

To perceive (someone or something) as having a lower value, quantity, worth etc. than what it actually has.

An estimate or perception that is too low.

an estimation that is too low; an estimate that is less than the true or actual value