It's better when people don't have to move at all and they can make their current home - if that's the one they want to remain in - work for them over time. People want to be safe and comfortable in their homes. They want them to be totally accessible - both getting into and out of the homes and moving about within them.
If someone has determined that their present home is something that needs to be replaced - because it's too small, too large, multiple stories, too many stairs to climb to the entrance (or too long or steep of a walk), too much property to maintain, a neighborhood where they don't feel safe, poor window design or location, narrow passageways, older or very little technology, or other issues that may be easier to fix by finding a different dwelling - there are many choices open to them but essentially two directions to pursue. People can look for and purchase a brand new home (free standing single family dwelling or multifamily townhome or condominium apartment), or they can find an existing home that meets their criteria. Additionally, the argument can be made that moving into an independent living facility (purchasing or renting) that is part of a larger campus satisfies the aging in place criteria.
There are many existing homes on the market that have served people well over the years that may meet the needs of someone looking to relocate. A never-before-occupied new home from a builder may offer a range of choices in wall colors, flooring, appliances, cabinetry, and floor plan layout. It might be in a neighborhood that is desirable. However, a new home is not the only option.
Generally for less money or with more designer features and upgrades already included for a comparably sized home, a seasoned existing home or one that is relatively new that compares well with a new home may be available.
Purchasing a "new" home as in a different one doesn't mean that it has to be new construction, and it doesn't mean that it has to be an existing home. It's personal preference along with many economic and emotional factors. Just know that there are several options in terms of size, features, price point, accessibility, technology, and other criteria that might make an existing home more attractive to someone looking for a different home.
If a "new" home is definitely on the horizon, make sure that it provides the access, freedom of movement, ease of use, convenience, general safety, brightness, and other mobility and sensory aspects that are going to make that home a good choice to remain in long-term. There's no point in purchasing something and then learning that it doesn't measure up to what was needed.
Before making a decision to change homes, a person should evaluate how well their present home can meet their needs - or be adapted or modified to do so and at what cost - and determine if moving is really something that is beneficial.
After all, aging in place means being able to stay in one's present home without the need to move. If there are concerns about how this can be done or what needs to happen, an aging in place consultant ("CAPS") can be contacted to help.