Most of my performing experience occurred around 1969-72 (jeez, that's 40 years ago !!?!?) when I sang on the street as my full-time occupation.

The "audience" was never a consideration, of course. The vast majority of my listeners would simply be passing in and out of earshot, not necessarily hearing either the beginning or ending of any song. Even those who enjoyed the music well enough to make a contribution did not necessarily linger (although, just about every day, someone without pressing business elsewhere would see fit to hang around for a while).

Theoretically, one could "get away with" singing a single number over and over in that situation, or at least to operate using a very limited repertoire of, say, a half-dozen songs. Few listeners would ever notice.

In practice, of course, one inevitably adds more and more variety to the program all the time, if only to keep oneself adequately entertained. Once, during that long-ago period, a friend asked me how many songs I knew, and I quit counting at 200; there were still quite a few more songs I knew and was ready to play ~ and to sing, as well, with all the words, and all the verses in the correct order, without cheat-sheets!

My streetsinging career came to a sudden halt when certain real-life issues intervened, and at some point I stopped playing even for my own amusement. I resumed playing/practicing maybe about 10-12 years ago, and then began "playing out" ~ just a little bit ~ three years ago, upon returning home to New Orleans from Katrina exile.

I have a one-hour spot once a month at a local coffeehouse. The first few times, I had barely enough material prepared to fill that measly little hour, and did pretty much the same set each time out.

Out of the 200+ songs in my former working repertoire, I certainly did not remember all of them, and of those I could recall, I did not necessarily still know all the lyrics, nor was I necessarily sufficiently practiced at all the intrumental parts.

As I gradually "relearned" some of my old favorites, and also worked up some "new" pieces ~ actually, old songs that I hadn't previously learned to play ~ I finally got to where I could vary my set-list from one monthly hour to the next.

I still repeat myself to some extent. There are about four or five songs I do almost every time out; they still seem to elicit positive reactions, indicating that the small audiences (which include a very few "regulars") don't seem to be sick of them yet. Of late, I've (temporarily?) settled on a regular opening number, because I find it easy to do well, and thus put myself in a sort of "comfort zone," confident and well warmed-up.

Confession: I rely, to an extent, on a stack of printed lyrics on a music stand I can just see out of the corner of my eye. In my earlier incarnation, I would never have considered resorting to such a "crutch"; of course, I was singing all day every day, and drummed all those lyrics into my head by sheer repetition. Things are much different nowadays; even on some long-familiar songs, I need an occasional glance at my notes to recall which verse comes next, etc.

If I were actually working at music for pay, and doing three or four 45-minute sets per evening at a bar with a few regulars but a larger number of tourists/transients, my only concern would be to avoid repeating myself on a given date ~ unless specifically requested to "do that one again," and/or if the crowd for the late set were entirely "turned over" from the folks who were listening earlier. From one date to the next, I'm sure that I would have to include many of the same songs each time out.

The opposite extreme is the situation MMario describes, where one is given the opportunity to perform ONE song, at an event that only recurs a few times a year. In such circumstances, I would hate to be asked to do the same old thing every time, and extend my sympathies!