If you want to get paid for performing music, you've got develop your craft; your music chops, your voice and your presentation or performance skills. Open Mic and jam sessions are great for getting started. You should play every chance you get. You learn every time you do.

1 Does playing open mics and other free gigs lead to getting paid work?

Rarely do open mics and free gigs lead to getting paid gigs. They help you develop your skill, your confidence and your reputation.

2 Who goes to open mic night apart from musicians?

Typically at open mics there is a small crowd local to the venue. The audience will be mostly other musicians who are often too focused on their set to hear or appreciate much of yours. BUT that does not have have to hurt your chance for success. Be as good as you can anyway, and play as if the room had 1000 music lovers. Give them your best.

3 Is the quality of music necessarily better at a paid gig than at an open mic?

Usually it is much better. There are always exceptions, but most open mics have a wide range of skills - some not so very developed - and most paid gigs have performers who have a proven level of entertainment value.

4 Are open mics reducing the number of paid gigs available?

I cannot see how. Open Mics typically offer folks who want a chance to play, a chance to play and bring in a few friends. They offer small clubs a chance to have a few people show up on an otherwise slow evening.

5 Is this a new thing or has it been going on in one form or other for ever?

Open mics have been around forever. They offer a starting point for people who are looking to get into paid performance. They offer a regular play to play to folks who just like to perform at that level and don't care about progressing.

Other comments

Open mics and jam sessions are great places to meet and "network" with other players. People who want to do what you want to do. You can meet people you like, and develop a music relationship with them. You can hear about other venues, other events and other players looking for people with just your sort of skill.