On average, players in the NBA take shots 6.5% further from the basket in the 4th period than in the 1st. This is a subtle, but consistent trend across all periods. 1.2% further in the 2nd than the 1st, 2.4% further in the 3rd than the 2nd, and 2.7% further in the 4th than the 3rd.
Most teams show the same trend, consider the graphic Average Distance of Shots by Period below:
Nearly all teams show an increasing distance by period, but there are some notable exceptions. A few teams like NYK, UTA, ATL, and ORL show an opposite trend.
It's not clear at this point what is leading this. Greater defense in later periods forces further shots? A greater need for 3-pts pushes shots away from the basket? A greater need for points in less time forces less ideal shots from further out? What about the exceptional teams where they get closer? What are these teams doing in the 4th quarter? Leaning more heavily on particular strengths or players? Tired players not driving to the net?
What is true at the global level and largely true at the team level is again reflected in the players. Here are the average distance for the top 100 scorers:
More noise, but the trend is still visible!