It sounds as though you may be raising pickling cucumbers rather than slicing cukes. The pickling varieties generally are low growing and have lots of rough bumps on the skin. They are picked when about 4 to 6 inches long and turn yellow if allowed to grow much beyond that. Whereas, slicing cukes are best grown on supports to get them off the ground... I have one right ow that's over 8 feet tall. the cukes dangle on the vine and can get to over 10 inches in length. They, too, will turn yellow, get soft and taste bitter if allwoed to mature to long, as scarett states...
I am sorry that people choose to be rude, as in the answer from the "colleyprior" person. When you start out gardening, as is my son, problems arise and it is nice to think you can post your question and have people either give you real answers and suggestions, rather than make fun or insult.
Apparently, that person, who claims you are "wasting" his/her time is being foolish by "wasting" more time in answering you rudely!! :-)
Good luck in the future.