Because on CD they get almost an unlimited amount of chances to get it right, live they only get one chance. Also there are many effects that can be used in a studio to make someone's voice sound better. Auto-tuners are used a lot to make people in tune, vocals are double-tracked to make them sound richer, etc. Most of these effects are not possible to use live.

As per Nitanrito case in point - Madonna

In defense of the performers (the truly good ones, anyway), aside from practice and effects, many conditions in a stage performance become physically and mentally different than in the studio. This has a vast effect on even the most experienced performer. The studio is (usually) more relaxed with an undercurrent of less time limits and more chances to get it, as well as the fact that you can physically position yourself whichever way you please (i.e.,John Lennon lay on the floor to sing "Julia"). Live often has less-than-perfect monitoring of the music and voice (no headphones) as well as limited physical choices (i.e. facing audience, walking, dancing, jumping, standing still when you'd rather pace, still breathing hard from the last number, etc.), so their physical ability to control their voices is often compromised. On stage, performers' vibrato often go a bit out-of-normal and their pitch control falters in a stage situation. You'll notice, though, that some perfomers often sound better at least a few shows into a tour, because they've gone through it a few times and may even listen to their previous shows to catch the problems and address them by changing technical stuff on stage or shifting vocal techniques in the songs ("singing around" the problem). Not all performers are geared to live performance as they are to the studio. Many, as I'm sure you may have noticed, are better at one than they are at another. Most Springsteen fans like him better live, while Steely Dan fans may prefer the albums (key words are "most" and "may"). Also, quite simply, bad moments on stage happen once, never to be heard again (unless they're stupid enough to put it on the "live" album). That fact often helps a live performer's confidence, as multiple takes and effects can bolster confidence in the studio. Depends on the performer. Of course, there are many artists who have no business in the studio OR on stage. But that's another question for another day.

Its called the magic of the recording studio. music, in a studio, is recorded under near perfect sound conditions. you can snap your finger and hear no echo. the sound stays right in front of you. some of the best recording equipment ever, is now in use. On stage is another situation, altogether. the accoustics, or surrounding sounds, are completely different and sometimes even very crude. this can present a problem , due to echo and feedback(the squeeling sound you hear, when a person talks into a microphone). this is why engineers arrive very early for a live performance. It is almost impossible to recreate the original sound, from the studio, in a live performance. in a studio, the singer(s) are stationary, when recording. a live performance is just that....live! Anything can and usually does.....happen!

Albums tend to sound cleaner because of the multiple takes, effects, a click tracks, and tons mixing and mastering... Live sound is a one take deal with "on the spot" mixing and with lots of things going on off/on stage. Live sound also tends to "rock out" a bit more with all the musicians taking liberties with parts and timing. Often, the band sounds better live while the singer sounds better on the album. Personally, I prefer both live because I see the raw talent of the musicians.

In the studio you can make everything you want to perfection .But on stage you could be faced with having to sing over the music and in turn there voice gets louder in attempt to sing or rap over the music and it just sound odd.

I love listening to music and even though most bands do sound worse singing live like... Eskimo Joe Performing: Black fingernail red wine At the ARIA awards... It's because when groups record they can use lots of different gadjets to edit their music! Hope that helped =D

After about 1960, this was true. Before that, what you hear on the record is essentially what you would hear in a live performance. Before 1940, there was no mixdown, editing, or special effects. Before 1925 it was direct-to-disc and acoustic. Editing was either extremely difficult or impossible. If the mistake is not too serious, the record would be released.

Sound editing. It's like air brushing a photograph. But with a sound.

Again I may get in trouble for being mouthy. I don't agree with your premise -- most singers do not always sound good regardless if live or not. As to ones that do -- I agree with with what others have written - all about the editing / refining process. I would submit that some are much more entertaining when seen as well as heard as our senses are not as independent as some believe. For some -- the visual, the company, even the odors can impact the way we value the entertainment. .