If when print ,the distance between nozzle and bed
is big (filament can’t stick at bed),you can reduce
the offset ,E.g:change -1.4 to -1.5,-1.8,-2.0.
If when print ,the distance between nozzle and bed
is too small(nozzle hit bed),you can add the offset
in marlin ,eg:change -1.4 to -1.2,-1.0,-0.8.