Myths
On this page we dismantle all of the myths of both G1 Megatron and Beast Wars Megatron.
Beast Wars Megatron never did anything.  He only sent his soldiers out to do the dirty work.
You have, of course, watched the show?  Because from this I see that you only buy the misconceptions of people who have only seen the first season.  Yes, in the first season, Beast Wars Megatron did not participate with his troops as he did later in the show.  But that does not man, by any stretch of the mind, that he was doing nothing.  Season 1  Beast Wars Megatron joined his troops in every major battle.  He joined them in the two battles of the "Beast Wars" two parter.  He joined them in "Call of the Wild".  He joined them in "Chain of Command", "Fallen Comrades", "Double Jeopordy", "The Probe", "Victory", "Dark Designs", "Spider's Game", "Possesion" and in "Other Voices".  Of the total 26 episodes in Season 1, he fought in all but one of the major battles (That being "The Trigger"). When the Predacons needed the support, he was always there.  And of those fourteen episodes he didn't fight, he was always working against the Maximals.  Instead of mindlessly attacking day after day, Megatron actually tried to assasinate a signle member of the Maximals.  And for the most part these schemese were successful. He did manage to make Rhinox a predacon.  He suceeded killing Optimus Primal.  He suceeded making the Maximals revert to their primal instincs.  There were only 7 episodes where he was idle.  And even then, that is only when he visibly did not do anything.  It would be logical to assume that he was also strategizing against the Maximals.
Season 1 Megatron, despite common myth, was an active member of the Beast Wars. 
Beast Wars Megatron lost the Beast Wars, just like every other bad-guy.
It is a staple of evil leaders to say that they have won a war, and then only lose it several seconds later.  Beast Wars Megatron seemed to follow this pattern at the end of Beast Wars.  However he is different in that he DID win. Not because he said won, but because the heroe said he won.  I now quote from "Master of the House"

Megatron:  Let us start with the Beast Wars.  They are over.  You lost.


and later in the episode

Optimus Primal:  I lost the Beast Wars.

It is official that Megatron won the Beast Wars, not because he said he did, but because there was concensus between the two  leaders that Megatron won.  He was acknowledged as the victor.