Whether tempering chocolate can be skipped depends on the recipe and desired outcome. Skipping it will result in chocolate that is dull, soft, and prone to bloom.
Tempering is the process of heating and cooling chocolate to stabilize its cocoa butter crystals. Untempered chocolate contains unstable crystals that cause it to melt easily, have a grainy texture, and develop a white coating called 'bloom.' When you temper chocolate, you're encouraging the formation of stable crystal structures. This results in chocolate that is shiny, snaps crisply, and has a smooth mouthfeel.
If you're simply melting chocolate to mix into a batter or sauce where appearance and snap aren't important, you can skip tempering. However, if you're using melted chocolate for coating, molding, or creating decorations, tempering is essential for a professional-looking and tasting result. Without tempering, the chocolate will be soft, dull, and prone to melting at room temperature.
If you're short on time or intimidated by traditional tempering methods, consider using 'seeding.' This involves melting most of the chocolate and then adding finely chopped, tempered chocolate (the 'seed') to encourage the formation of stable crystals. This is a simpler and often more reliable method for home cooks.