Why am I seeing low sequencing output even though I’m using the same loading concentration for this same library as before?

Question: Why am I seeing low sequencing output even though I’m using the same loading concentration for this same library as before? Answer: Unexpected low output from a previously optimized library is usually caused by a change in library quality or a mistake in library preparation. Common contributors include improper denaturation, dilution or quantification errors, DNA loss from non–low-bind plasticware, degraded library, upgraded AVITI™ system, or compromised reagents.