Once lost, the likelihood of regaining trademark rights is slim. Names like 'escalator' and even 'petrol' began life as registered trademarks but have now become "generic." Constant and careless misuse, due to inappropriate monitoring or inactivity by their owners, results in them becoming merely the name of goods.  Eventually, failure to maintain the distinctive character of a mark can mean the loss of exclusive rights to it.

Protect your trademark. 

1) Establish preferred vendors that understand your trademark and how it can and can not be used.

2) Adhere to brand guidelines.  NO EXCEPTIONS!

3) Control the availability of products with the trademark by using a Company Store(shameless plug)