Final answer:
The fossil record is incomplete because many species did not die in the right conditions to be fossilized, and many fossils have not been found by paleontologists.
Step-by-step explanation:
A possible weakness of the fossil record is that many species probably did not die in the right place at the right time to be captured in fossils, and many fossils will never be found by paleontologists. This means that the fossil record is very incomplete and doesn't represent the full diversity of life that existed in the past. For example, the soft parts of organisms almost always decompose quickly after death, so only the hard parts like bones and shells have a chance of becoming fossils.