This is especially true of manufacturers that must complete a changeover on a tight schedule. Many management people are not aware of changes in patent law that allow triple damages. A company is legally responsible for knowing about current patents. Ignorance is not an acceptable excuse. They can be forced to pay triple damages and your attorney fees.
Juries tend to take a dim view of companies stealing from individual inventors.
They are especially sympathetic when the company is large or foreign-owned. If polite persuasion doesn't work, then you must play hardball. Gather as much information on an infringing company as possible. Contact past employees. Companies that steal intellectual property usually shaft employees, and an ex-employee that has not been treated well can be a goldmine of information that will make your infringement case easier to pursue.