Which is partially true, unless the pipeline stalls or gets bubbles. Stalls One of the tradeoffs with making a deep pipelining is what is called a stall . This is what a stall could look like. So there is a real balancing act on thruput vs. latency, and in what it takes to keep pipes filled. Of course dependencies cause pipeline stalls, but there are many things an instruction is dependent on.
Lets look at some of the things that can stall a processor and slow work down.
Many instructions are dependent on another instruction or data being loaded or stored before they continue. So the pipe sometimes has to wait for a previous instruction to finish loading, or storing its work, before things can go on. Each instruction has to be loaded, and have all its data loaded. You use shortcuts to reduce the hit on pipeline stalls. Conclusion Pentiums versus PowerPC's Pentiums are a complex instruction set, that required many stages in their pipes.