Everything. Everything affects the quality of the queen. This is why I'm obsessive about the process of queen rearing. I want THE best quality queens possible. We're leaving genetics out of the equation here to focus on physical development. Genetics is highly important, don't get me wrong. From day one, larvae intended to be queens are fed royal jelly. Workers are switched to a dilute mix around 24 hrs of age. This is where the path diverges. The first question would be, at what age was the larvae fed royal jelly? Did they start receiving worker mix only to be abruptly switched to pure royal jelly? It happens often in walkaway splits, emergency worker comb queens from accidental queen death, or when larvae older than 24 hrs are grafted. It comes as a surprise to many that someone would say this about walkaway splits, which are still a popular method of queen rearing. However, this is old news. GM Doolittle, the father of modern grafting noticed and pinpointed this issue in the 1800's. (reference his book "Scientific Queen Rearing" for further info) If this occurs her development is compromised. Queens are obviously vastly different than workers. Their entire function and physiology are changed by their diet. This epigenetic change alters her DNA. Wrap your mind around that. When her development starts it needs to be unimpeded. Graft only newly hatched larvae to avoid queens which may have been fed to develop into workers. If you can barely see them, they're perfect. Secondly nutrition is a huge factor. If you pay attention to when bees naturally raise queens, you will notice it always occurs during nectar and pollen flows. The workers' glands that produce royal jelly are swelled and productive, stimulated from incoming nectar and pollen. Also take notice that colonies that throw nice swarms typically have large populations. When setting up a cell builder to produce queens, we need to replicate these ideal conditions. Only raise queens when they are raising queens and there is a flow. This takes care of the often overlooked portion of the equation as well, drones. Nectar and pollen flows stimulate drone production. If you follow their lead, they will let you know when the time is right. I use large queenless cell builders to produce my queens. When the population is large, they have much more resources to devote to this vital endeavor. I also feed my cell builders constantly while they are constructing the cells and feeding my queens. It's not unheard of to have several days back to back of rainy weather in spring. Since I was feeding the whole time, regardless of the fact they are unable to forage and bring in nutrition, they have access to food. We don't want any skinny ladies here. We want them thick, with big booties. Stay focused guys, we're talking about queens still. When you have queens that are well fed, their ovaries are fully developed and capable of laying large quantities of eggs. Small under developed queens lack fully developed ovaries and are incapable of laying enough eggs to produce a large population of bees. Small bee populations are worthless. They won't produce surplus honey, there's not an abundance of brood frames to make nucs, and they're weaker and less able to fight off pests and diseases. Queen quality obviously can affect your entire operation. After you have raised quality queens, be sure to protect your investment. Don't bank queens unless absolutely necessary. Often they are neglected, or their tarsi (foot pads) are chewed. Introduce them to their new colony asap. Shipping is also a huge stress on queens. They're tossed about with varying temperatures, and are out of the care and warmth of the hive. She is also cooped up and not able to be laying eggs as she would be doing if left alone in her colony. Shipping stress affects queen quality as well. If you're raising your own, you've eliminated that risk as well. Don't skimp when it comes to your queens. They are the foundation our operation is built upon.