Over-explaining is a tiresome habit in conversation and presentations.
Giving context and background prior to the delivery of what needs to be said is necessary, but should be done with precision. There’s no need to give an entire history when a simple one will do.
Also, it’s a chore to have to hear further explanations while the delivery is happening. Stopping a conversation in mid-point to give even more background is either an indicator of needing work on the delivery, or completely missing the bored social cues from others.
A worst case scenario is one who enjoys hearing themselves speak and assumes others want to listen, regardless if what they’re saying is useful.
When people are interested in what you have to say, they will inquire further. If they don’t have access to you directly, they will find the means to contact you indirectly. If there is one fault that cannot be levied towards our communication devices, it’s the ease of connecting with others.