I would like to know what the quality ranges are for Nanoplot and what criteria are used to determine these quality ranges or obtained quality results. my results were:

sample 1
General summary:        
Mean read length:                569.0
Mean read quality:                14.0
Median read length:              221.0
Median read quality:              13.6
Number of reads:              18,713.0
Read length N50:               1,741.0
Total bases:              10,648,246.0
sample 2
General summary:        
Mean read length:               2,283.7
Mean read quality:                 14.0
Median read length:             1,390.0
Median read quality:               13.8
Number of reads:              161,819.0
Read length N50:                4,108.0
Total bases:              369,538,332.0

Is my quality data good or bad?