According to the Florida Uniform Traffic Code section 316.2065, bicycle riders are generally expected to ride in the bicycle lane on roadways if they are traveling less than the normal speed of traffic. Bike riders are allowed to leave bike lanes when making a turn at intersections, when passing another bike, or when reasonably necessary to avoid hazards. When riding on the roads, bicyclists are also expected to follow basic rules of the road, including stopping at traffic lights.
Bike riders aren't the only ones with obligations. Drivers need to respect the rights of riders to be on bike lanes and to be on the road in general. Unfortunately, not all drivers do a very good job at that. Tampa Bay Times reported the death rate for bicycle riders in Florida is the highest in the whole nation. Drivers (and bike riders) need to follow the rules to try to bring crash rate down, especially rules designed to make it possible for motorists and bicyclists to share the road safely.
While Florida law tells bicycle riders when they can, and cannot, stray from bike lanes, there are also laws for drivers to try to make it safer for bicyclists and vehicle drivers to share the road. For example, Florida Statute 316.083 explains the rules when drivers pass other motorists. According to the relevant statute, a driver who is passing a bicycle must pass at a "safe distance." A "safe distance" is defined as leaving no less than three feet between the vehicle and the bike.
Drivers who get too close to bicycle riders could cause an accident to happen that injures the rider. That's why this law exists to govern how the road is shared. Likewise, bicyclists who unexpectedly stray from bike lanes and into traffic are also a cause of crashes, which is why Code Section 316.2065 explains when and why bikers can get out of their designated lanes.
Drivers of cars and bicycle riders often share an uneasy relationship on the road, in spite of these and other rules trying to improve safety. Slate published an article explaining why many motorists "hate" cyclists, including because of the irresponsible behavior of some bikers and because the idea of biking as a means or transportation is still foreign. On the other side, many cyclists have reason to dislike and fear drivers, especially in light of Florida's high death rates for riders. The antipathy between bikers and drivers of cars can sometimes help to contribute to rising accident rates if riders or drivers fail to obey all of the rules and show respect to each other on the roads.
Bicycle riders and drivers owe it to each other to try to share the road in a safe way so crash rates can go down. The law sets forth the framework for what each party's obligations are, and if either party fails to fulfill those obligations, that person should be held accountable for accidents resulting from failure to share the road.