One of the causes of hesitation is when practicing a section students don’t overlap sections and a result of this they hesitate when going from one section to another.
It is very important that when practicing you overlap sections. Sometimes a single note added at the end of a bar is not enough. Use a whole bar as overlap (or even a whole phrase). This means adding the first bar (or first phrase) of section 2 at the end of section 1, and adding the last bar (or last phrase) of section1 at the start of section 2. Once you can do these two (enlarged) sections without problems, you should have no hesitation when joining them.
Hesitation typically occurs for two other main reasons:
1. You do not know the music well enough, so you do not know where to go next. This is particularly the case with fast passages. The way out is to memorize the music (and by this I do not mean being able to play without the score – you can use the score as a reference even though you have memorized the music).
2. A far more common reason however, has to do with too many options. This is a technical problem. As you repeat a passage, if you keep changing the fingering, or if you use a different movement every repetition, your brain will be undecided about which option to use when it gets to the passage in question. Therefore you hesitate. So when doing repeats of the offending section, make sure they are indeed repeats, that is, you must repeat exactly the same movements and use exactly the same fingerings. Fingerings and movements are not written in stone. Spend time investigating the best movements/fingerings for your physicality and for the musical result you are after. However once you reach a decision, stick by it and use your focus and concentration to make sure that you are indeed repeating these movements and fingerings. In other words, hesitation may be simply the result of sloppy practicing.