How many live deals during analyst stint?

There is effectively zero an analyst can do about whether a deal closes. So many things can go wrong at every stage of a sell-side that I don't place any credence on how many deals an analyst closes during their recruiting window, but do place a lot on their group and perceived deal flow. For deal flow, just look at the league tables for the highest volume M&A shops in a given vertical and compare it to their analyst headcount for that vertical. Deal experience is a function of deal sizes, complexity, and volume. I would for example expect someone at a top MM firm like Jefferies or Blair or Baird to have far more sell-side M&A experience than someone at a lower-tier BB like UBS or DB just due to the volume of those shops churning out deals. The strength of your deal experience is ultimately idiosyncratic based on how a firm and its deal teams are structured, but league tables for a vertical are a decent proxy for deal flow, especially for non-large balance sheet banks (ex. Wells Fargo). There are diminishing returns to deal flow at some point, but generally you learn something from every sell-side you touch.

With all that being said, most of what you'll learn about investing you'll learn in PE. Everything is largely teachable. If you've only been on pitches it's not ideal, but as long as you can ramp up you'll be fine. Nobody is going to ding you for your deal experience once you have the job as we understand it is out of your control as an analyst. It will likely be harder to get the job though, since the ability to think like an investor is easiest to develop while working on live deals. Have had associates come in with minimal to no deal experience and ramp up fine, and have had associates with great deal experience be terrible. It all comes down to your actual learning pace once you hit the desk.