Servicing helps prevent breakdowns by ensuring everything is working within its limits.
![Burnt resistor from damaged valve 1 burnt resistor as result of poor servicing](https://sickamps.com/wp-content/uploads/2017/03/burnt-resistor-as-result-of-poor-servicing-768x1024.jpg)
Regularly checking of valve biasing can avoid an amp being continually overloaded and stressing the amp out. This resistor had burned and blew as a result of the valves going short and damaging. The remaining valve was very worn, with regular maintenance and servicing the valve should have been changed quite a while ago!