How many Botox treatments are usually required to maintain stable effects?

I recently became interested in Botox treatments and have been looking up information. However, the more I research, the more questions I have, so I would like to ask those with experience.

In particular, I am wondering if a single Botox injection is sufficient, or if I need to receive multiple sessions. Some articles say that consistent injections are necessary for good results, while others say that getting them only when needed is sufficient. In reality, I am not sure which is correct.

If this is my first time getting Botox, I would like to know how often maintenance is typically performed and how many sessions are needed to achieve satisfactory results. I have heard that Botox reduces muscle size, so I am also curious if receiving it repeatedly leads to more significant changes.

I would also like to know what I need to prepare before getting Botox and what precautions I should take after the procedure. I am curious if factors such as exercise, alcohol consumption, or saunas have any impact. I would like to hear the experiences of those who consistently maintain their Botox regimen or have received treatments for a long time. I would appreciate it if you could share your opinions on the recommended number of treatments, as well as your actual satisfaction levels.