Is there a reason for using MAXA/MINA, also you have far too many
parenthesis..
You could for instance name parts of the formula like
=OR(MAXA($B$12:$U$12)-$U$14)/(MAXA($B$12:$U$12)-MINA($B$13:$U$13))>90%,(MAXA
($B$12:$U$12)-$U$14)/(MAXA($B$12:$U$12)-MINA($B$13:$U$13))<=10%)
do insert>name define, let's call it Part1
then you can use
=IF(Part1,(((SUM($S$14:$U$14)/3)*6+(SUM($R$14:$U$14)/4+(SUM($Q$6:$U$14)/5)+(
SUM($M$6:$U$14)/9)+(SUM($L$6:$U$14)/10)+(SUM($B$14:$U$14)/20)))/11))
do the same with the Sum part, call it Part2
then use
=IF(Part1,Part2)