Planets predicted from our debris analyses, compared to known planets and those inferred to be forming in protoplanetary discs (Sect. 5.1.1). Small black circles are known exoplanets from Exoplanet.eu, and large circles are Solar System planets. The left plot shows the planetary populations inferred from our debris analyses; green diamonds and blue crosses are the planets required to sculpt the discs if sculpting is performed by one or multiple planets, respectively (Sects. 3.1 and 3.2). Red circles are planets required to stir the discs (only systems with resolved discs are shown; Sect. 4.2). The plot shows that debris disc morphologies imply planetary populations that are poorly explored with current instruments, so the hypotheses that planets sculpt and stir debris discs are consistent with the lack of planet detections in these systems. Right plot: Comparison of our planets inferred from debris discs to those inferred to be forming in protoplanetary discs (black crosses; Lodato et al. 2019). To make the plot clearer, we have replaced our individual planet predictions with rough areas representing the three populations. Our planetary population inferred from debris discs well matches the population inferred to be forming in protoplanetary discs; if the forming planets remain in situ, then they could later join the population responsible for sculpting and stirring known debris discs. Alternatively, it is possible that the forming planets rapidly sculpt debris discs before migrating inwards. Error bars are omitted for clarity but can be seen in our other figures.