stronger the affinity of the promoter for RNA Polymerase likely is.

In the absence of other regulatory elements, the default state of a bacterial transcript is to be in the "on" configuration, resulting in the production of some amount of transcript. This means that transcriptional regulation in the form of protein repressors and positive control elements can either increase or decrease transcription. Repressors often physically occupy the promoter location, occluding RNA polymerase from binding. Alternatively a repressor and polymerase