B737-800
Flight Crew Air Transport Pilot (ATP)
Flight Crew Total 15000
Human-Machine Interface
Aircraft Equipment Problem Less Severe; Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Returned To Clearance
Aircraft; Human Factors
I was the pilot monitoring and we were cleared to descend via the Arrival into ZZZ.  The bottom altitude is 10;000 feet which was set properly.  The 'ALT INTV' button was pressed once the clearance was received which I believe cancelled the first altitude constraint of Fix ZZZZZ at or above FL240.  We ended up crossing Fix ZZZZZ approximately 1;000 feet low.  The rest of the crossing altitudes were all made without incident and we landed safely.  The center controller did not say anything.  Active pilot monitoring would prevent this from happening in the future.  I will pay closer attention to each altitude when climbing or descending from now on.
A B737-800 air crew upon receipt of a descent clearance; pressed the 'ALT INTV' button. In doing so the first altitude constraint was deleted and they crossed it 1;000 feet low.