When used in something going well you could say 'It went down like a lead balloon' that's means its successful right?
But when you use it in a negative context, like giving someone bad news eg; 'I had to make someone redundant today - it went down like a lead balloon' that surely indicates something unsuccessful?
If you think about the image - a balloon made out of a heavy metal - it is only ever going to go down, and never float, so comparing something going down 'like a lead balloon' means it had a negative impact.
Of course, when Keith Moon told Jimmy Page that his 'New Yardbirds' project would go down 'like a lead balloon', it gave Jimmy the idea for a name for a brand new band.
Your Faux-pas must have led to some amusing exchanges, booldawg.
'Thanks for the present, went down like a lead balloon in my house' says our hero, all happy like.
And the other bloke thinking, 'Cheeky basket, that's yer last'
///Entwistle said of forming a band with Jimmy Page and Steve Winwood and he would name it "Lead Zeppelin" because it'll go over like a lead balloon". The spelling of "lead" was changed to avoid confusion over its pronunciation.///