Some examples off the top of my head - and apologies if you or anyone reading this actually live in these places, but I won't mince words ;)

Seattle: downtown is absolutely deserted during non working hours because of a foolish desire to separate residential and commercial areas. Businesses in these zones suffer since they can either only cater to office/daytime traffic or residential/nighttime traffic and never both. Downtown is perceived (rightly or wrongly) as dangerous during off-hours because it is completely deserted.

Even in residential areas this doesn't get much better. Belltown, a highly urban neighborhood full of highrises, has practically empty streets. You can walk down a main thoroughfare in that neighborhood in the middle of the afternoon on Saturday and see maybe 4-5 people as far as the eyes can see. The design of these buildings are largely monolithic with attached parking, creating a relative dearth of retail and commercial use. There is still no grocery store in the neighborhood since literally none of the many highrises were designed with large enough retail spaces to house one - which might explain the lack of street life - you must use a car to access even basic supplies (or rely on modern workarounds like delivery grocery). There are no hardware stores, no grocery stores, a single run-down pharmacy... it's as if someone heard the word "retail" and thought "bars and restaurants" only.

As compared to another Seattle neighborhood, Fremont, which is also urban, but features high foot traffic, the presence of both housing and offices in the neighborhood, a plethora of businesses supporting everyday needs, and a highly active street life. Or Capitol Hill (arguably a neighborhood in decline) where the neighborhood is anchored by the community college, major grocery stores, and nearby hospital staff, creating high foot traffic (street "watchers") at all hours.

Vancouver (Canada) suffers from the same problems. Yaletown, an upmarket urban neighborhood full of highrises, is nearly deserted except a single street that leads to the transit station. Much of this is because said highrises have zero retail or mixed-use accomodations, creating huge dead zones where the only people traversing it are the ones heading directly toward, or directly away from, home. It's not quite as bad as Belltown in Seattle, but it's not great.

In fact other neighborhoods in Vancouver's urban downtown core suffer even more egregiously. Many of the older (read: 90s) buildings were constructed before any substantial transit coverage as added to downtown, and their residents were car-reliant to the point where the streets surrounding mid- and high-rises don't even have sidewalks (see: the West End), and some of these buildings lack even basic street-facing entrances (street frontage reserved for garage facilities, naturally), forcing pedestrian visitors to come through the side like second-class citizens. Even though transit coverage in these areas is now excellent, the lack of street traffic remains because of the fundamental architecture of the streets and buildings.

I've also lived in Toronto and some of its neighborhoods suffer from this too. Practically the entire waterfront area is a veritable wasteland of highrise condo buildings. Clean-cut glass skyscrapers loom over almost-deserted streets because of insufficient (and sometimes a complete lack of) retail and commercial spaces. Take a car from the garage to access almost everything you need for everyday survival. Their only saving grace (and source of street activity) are the commuters waiting for streetcars or buses.

Anyways, rant aside, here are some commonalities I see between these places:

- A rejection of mixed-use developments. The primary driver of emptiness here is because there is nowhere to go - no grocery stores, no coffee shops, no nothing. Where mixed-use is embraced, everyone wants to host trendy businesses like bars and restaurants (which help improve property value for the building) but not the everyday businesses (pharmacies, grocery stores, barbers) that drive the most street traffic and serve as traffic anchors.

- A large-lot monolithic style of development. These buildings feature large set-backs from the sidewalk, with hedges, fences, or low walls facing the sidewalk. The implicit message here is "keep walking, bud", instead of "come on in and visit [X]". More importantly, because these buildings tend to be whole-block developments, when a single building fails to embrace commercial use or is otherwise poorly designed, it creates a massive dead zone on the street that seems to go on forever. IMO large-lot "complexes" are the worst thing to happen to American urbanism, ever.

- A disproportionate amount of space dedicated to parking. Many of these buildings lack commercial and retail space because it's occupied by parking structures. Many of these buildings lack even proper residential street frontage because that space is for a garage gate.