The idea behind this process is simply to build the product and test it every day. Here are some of the ins and outs of this simple idea. If there's no heartbeat, the project is dead. Different developers' code is allowed to get a little out of sync between these pulses, but every time there's a sync pulse, the code has to come back into alignment. When you insist on keeping the pulses close together, you prevent developers from getting out of sync entirely.
Some organizations build every week, rather than every day.
The problem with this is that if the build is broken one week, you might go for several weeks before the next good build. When that happens, you lose virtually all of the benefit of frequent builds. Check for broken builds. For the daily-build process to work, the software that's built has to work. If the software isn't usable, the build is considered to be broken and fixing it becomes top priority.