Repeating a talk is a good thing. You will become more confident in your delivery - the third audience to see that talk is likely to see a far more polished version than the first!
New presenters often feel that they need to write a brand-new talk for each conference they are invited to. Unless your job is giving presentations, or you are being paid very well for each talk you give, it is unlikely that you will be able to keep this up if you do more than a couple of talks per year.
You’ll therefore find that most presenters have one or a few talks that they reuse for a period of time, before retiring them and moving onto something new.
Repeating a talk is a good thing. You will become more confident in your delivery - the third audience to see that talk is likely to see a far more polished version than the first! As a presenter it will help you to learn about different audiences too - there can be a big difference in the way that audiences in different cities, never mind different countries react. I enjoy the process of refining a talk over time, adding a better explanation for something that comes up in Q&A or on Twitter later, or reworking a section to add some new information.
I have had some talks that have become a very good example of Theseus’s Paradox. They had the same title, but is it the same talk if every slide and example has been replaced at least once?
Tips for reusing material
For technical talks in particular, it is often possible to create your talk as a series of blocks. I tend to use blocks of 5 or 10 minutes, that can be included or left out depending on the length of talk needed, and sometimes the audience I will be speaking to.
For example, I might have a block which is an introduction to the subject. However, I know that the audience for the talk at a certain conference is pretty advanced and are likely to know the basic material. I can take that out, and instead add a block of more advanced material nearer the end of the talk.
I might have two ways to teach a concept - one more suitable for people who are designers and likely to prefer a visual explanation to a very technical one.
I have talks that can be given in 30, 40 or 50 minute versions. It is worth making sure you rehearse each variant so as to avoid being surprised by your next slide!
The key thing when creating a talk for different lengths is that it still stands alone at the shorter length, and isn’t full of padding for the longer version. Take advantage of your extra time to add an additional section, or expand an example to give more detail than is possible in a quick fire 30 minutes. I find this approach to creating flexible talks works well between 30 and 50 minutes. Very short talks usually need to be so focused that I have to write them as short talk from the outset, and very long talks - for example my one hour An Event Apart talks - I take a slightly different approach. An hour is a lot of material and needs a great deal of structure to hold the attention of listeners.
What if you are asked for a brand new talk?
There are conferences that sometimes ask presenters for new material. However it is pretty unusual, conference organisers are generally aware of the amount of time creating a good talk takes. They know that any compensation you might be receiving is unlikely to cover the cost of all the hours of creation and rehearsal time.
How you respond to a request for a new talk is up to you. Unless I was being paid for the creation of the material I’d probably not agree to create something completely unique for an event. I might agree to use an event as the first time I gave a new talk however, new talks have to start somewhere!
Other ways to reuse your content
If you have put a lot of work into researching and creating a talk, don’t forget that there are other ways to share that material. I always publish the code examples used in my talks on CodePen for example. You could publish a full transcript of the talk, or use it as the basis of a series of blog posts. It is likely that there was research that informed the talk but was not used on stage - this can also be a great article or post either for your own site or to submit as a written piece somewhere. All of this can help the time you spend preparing for a talk more useful, in addition to giving you great information to share with your audience I the resources for your talk.