A chain saw for most is a rarely used item. Was running fine when it was put in the back of the shed 3 years ago.
Ice storm, tree down, I know I've got one around here somewhere - pull and pull and pull and it never starts.
It's one of those things that runs best on fresh gas/oil.
Oh, and a sharp chain. Again, most get put away after use - and the chain is dull. A dremel tool with the chain kit and you can have it sharp as new in 10 minutes.
Edited to add - I own a Poulan and baby Homelite