Cats love new things. Bring something new in the house and every cat will come out to give it a thorough inspection. That is especially true when you have to put that new thing together, as I did last night with a new shelving unit. All three of our cats were busy investigating every nook and cranny.
After it was mostly put together, they each had to get on it to test for structural deficiencies. There was even a bit of a disagreement when two of the inspectors found that their work areas overlapped.